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Molecular-Level Interactions in Binary Mixtures of 1-Ethyl-3-methylimidazolium Ethylsulfate and Propane-1,2-diol: The Interplay between Intermolecular and Intramolecular Hydrogen Bonding
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Molecular-Level Interactions in Binary Mixtures of 1-Ethyl-3-methylimidazolium Ethylsulfate and Propane-1,2-diol: The Interplay between Intermolecular and Intramolecular Hydrogen Bonding
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  • Md. Ahad Ali
    Md. Ahad Ali
    Department of Chemistry, University of Dhaka, Dhaka 1000, Bangladesh
    Department of Chemistry, Jashore University of Science and Technology, Jashore 7408, Bangladesh
    More by Md. Ahad Ali
  • Md. Abu Bin Hasan Susan*
    Md. Abu Bin Hasan Susan
    Department of Chemistry, University of Dhaka, Dhaka 1000, Bangladesh
    Dhaka University Nanotechnology Center (DUNC), University of Dhaka, Dhaka 1000, Bangladesh
    *Email: [email protected]
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    Orcidhttps://orcid.org/0000-0003-0752-1979
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ACS Omega

Cite this: ACS Omega 2023, 8, 36, 32690–32700
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https://doi.org/10.1021/acsomega.3c03457
Published August 30, 2023

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Abstract

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In this study, volumetric properties of an ionic liquid, 1-ethyl-3-methylimidazolium ethylsulfate ([C2mim]C2H5SO4), propane-1,2-diol, and their binary mixtures were studied by measurements of density and viscosity. The excess molar volume (VmE), dynamic viscosity deviation (Δη), and excess molar Gibbs free energy of activation for viscous flow (ΔGm*) were calculated and fitted with the Redlich–Kister (RK) type polynomial equation. The results suggested that intermolecular interactions are weaker in the mixture compared to the pure components and the interactions decrease with increasing mole fraction of [C2mim]C2H5SO4. The thermodynamic activation parameters were also calculated from the Eyring equation, and their variations with mole fraction of [C2mim]C2H5SO4 were correlated to the molecular-level interactions. The near-infrared (NIR) spectroscopic measurements were carried out in the temperature range from 293.15 to 333.15 K. The raw NIR data were analyzed further by two-dimensional correlation spectroscopy and principal component analysis. When [C2mim]C2H5SO4 was introduced to the propane-1,2-diol system, the stronger intermolecular hydrogen bonds were destroyed. Propane-1,2-diol and [C2mim]C2H5SO4 produce some weaker hydrogen bonds, but the effect of breaking hydrogen bonds predominates. On the basis of volumetric and NIR spectroscopic investigations, molecular-level interactions are predicted. The interplay between intermolecular and intramolecular hydrogen bonding decides unique molecular-level interactions and dictates enhanced thermodynamic properties of the binary mixtures to make them tunable for a multitude of applications.

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Introduction

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Ionic liquids (ILs) are one of the most intriguing breakthroughs in solvent chemistry. The terminology “ILs” alludes to solvent materials that are only composed of ions but are liquids below 373.15 K. ILs received an upsurge of interest because of their eco-friendly characteristics and superior physicochemical properties which include relatively low melting point, non-flammability, imperceptible vapor pressure, wide electrochemical window, high electrical conductivity, immense thermal stability, wide liquidous range, a great capacity of dissolving a variety of inorganic and organic substances, and even the flexibility of tailoring the structure of cations and anions to get optimum physicochemical properties. (1,2) These extraordinary properties have made ILs pragmatic in industries as electrolytes in modern energy devices, solvents in chemical reactions, (3,4) extraction, (5,6) separation, (7,8) electrodeposition, (9) medium of nanomaterial synthesis, (10,11) enzyme catalysis, (12,13) and gas capture. (14)
Despite a number of superior features of ILs over conventional organic solvents, their applications have become dwindled because of their extravagant nature and erratic properties like high viscosity, hygroscopic nature, etc. (15) However, the prospect of tuning the properties by tailoring the ions retained the hope of overcoming the problems. Tokuda et al., through their systematic study of aprotic ILs, established that their physicochemical properties depend on their structural components and may be altered by manipulating the constituent cation, anion, and sub-constituent alkyl chain proportions. (16−18) They utilized the effective ion contribution and the amount of force balance between multiple interacting forces to characterize the transformations of physicochemical characteristics. Another way of adjustment of physicochemical properties is the preparation of binary mixtures of ILs with conventional molecular solvents. Pereiro et al. calculated excess molar volumes, changes in refractive indices upon mixing, and isentropic compressibility from measurements of densities, sound velocities, and refractive indices of binary mixtures of ethanol with 1,3-dimethylimidazolium methylsulfate, 1-butyl-3-methylimidazolium methylsulfate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-hexyl-3- methylimidazolium hexafluorophosphate, and 1-methyl-3-octylimidazonium hexafluorophosphate at T = 293.15 to 303.15 K. (19) AlTwaim et al. investigated the impact of alkyl chain length on the physical characteristics of binary mixtures of propane-1-ol, butane-1-ol, and pentane-1-ol with 1-ethyl-3-methylimidazolium methylsulfate. They measured the viscosities and surface tensions and calculated the corresponding deviation properties and excess Gibbs free energy using the experimental data. (20)
Physicochemical properties of the binary mixtures of [C2mim]C2H5SO4 with molecular organic solvents including water, methane-1-ol, ethane-1-ol, propane-1-ol, propane-2-ol, acetone, acetonitrile, propylene carbonate, dichloromethane, and sugars are available in the literature. Miaja et al. reported the density data of binary mixtures of [C2mim]C2H5SO4 with water, (21) Gonza’lez et al. reported the densities, velocities of sound, and refractive indices of binary mixtures of [C2mim]C2H5SO4 with methane-1-ol, propane-1-ol, and propane-2-ol. (22) Lehmann et al. reported the density data of binary mixtures of [C2mim]C2H5SO4 with acetone, acetonitrile, propylene carbonate, dichloromethane, methanol, ethanol, and water. (23) Kiefer et al. investigated molecular-level interaction between [C2mim]C2H5SO4 and acetone analyzing peak shifting induced by acetone and the excess infrared (IR) spectra of IL. They showed that rather than interacting with ion pairs, acetone forms hydrogen bonds with the hydrogen of the imidazolium ring. (24) Reddy et al. predicted molecular-level interactions of the binary mixtures of [C2mim]C2H5SO4 and 2-methoxyethanol using both thermodynamic and IR spectroscopic studies. (25)
Volumetric and viscometric studies of a series of dialkyl- and trialkyl-substituted imidazolium-based ILs having [NTF2] anion with a series of molecular solvents like ethylene glycol, diethylene glycol dimethylether, triethylene glycol dimethylether, etc. (26−28) and volumetric properties and spectroscopic studies of binary mixtures of various ammonium- and imidazolium-based ILs with a series of alcohols were used to predict molecular-level interactions. (29−31)
Near-infrared (NIR) spectroscopy has been extensively used to investigate molecule-level interactions in binary mixtures of many ILs and molecular solvents. The binary mixtures of ILs not only improve the properties of the medium for task-specific applications but also reduce the expense. Alcohols with −OH groups in the structure are susceptible to hydrogen bonding and hence have immense prospects for tuning the physicochemical properties. We intend to use NIR spectroscopy to gain a qualitative and quantitative understanding of the interactions between the numerous hydrogen-bonded species present in binary mixtures of [C2mim]C2H5SO4 with alcohols. We have already reported the molecular-level interactions between [C2mim]C2H5SO4 and a monohydric alcohol, propane-1-ol, and observed that when the IL is added to propane-1-ol owing to the fewer hydrogen bonding sites the intermolecular hydrogen bonds easily undergo disruption and solvate the ions to yield negative values of excess thermodynamic properties. (32) It is a burgeoning question, whether an alcohol with multiple −OH groups in the structure exhibit similar behavior and influence physicochemical properties in an identical fashion. To gain a deep insight, it is, therefore, crucial to understand molecular-level interactions of the IL with a dihydric alcohol and compare and contrast with a monohydric alcohol in terms of enhancement of thermodynamic properties of the binary mixtures. In this study, we used [C2mim]C2H5SO4, propane-1,2-diol, and their binary mixtures for a detailed analysis. The variations in excess molar volumes, dynamic viscosity deviations, and excess molar Gibbs free energy of activation for the viscous flow of binary mixtures with composition have been explained using spectroscopic observations to develop a fundamental knowledge-base on interaction in the molecular-level and consequent enhancement in thermodynamic properties for systems of this kind.

Experimental Section

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The IL, [C2mim]C2H5SO4 obtained from Merck at ≥95% purity, was used after vacuum drying and the water content was found 1.027 wt % in the ambient condition determined by the Karl-Fischer titrator (Metrohm 860-KF). The propane-1,2-diol at ≥99.55% purity was obtained from Merck and was used without further purification. The gravimetric method was used to prepare the binary mixtures with the following compositions given in [C2mim]C2H5SO4 mole fraction: 0 (pure propane-1,2-diol), 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, and 1 (pure [C2mim]C2H5SO4).
The measurements of densities and dynamic viscosities were carried out in an Anton Paar (DMA 4500 M) densimeter having a standard deviation of ±0.00001 g cm–3 and an Anton Paar (Lovis 2000 ME) microviscometer with a standard deviation of ±0.001 mPa s, respectively, automatically thermostated within ±0.01 K by a built-in Peltier device in the temperature range from 293.15 to 333.15 K with 5 K intervals. A Fourier transform spectrophotometer (FTIR/NIR, PerkinElmer, USA) was used to record the NIR spectra in the range 4000–10,000 cm–1 at 2 cm–1 resolution. Temperature-dependent NIR spectra of materials were measured using a highly sensitive liquid sampling cell with a pair of rectangular CaF2 windows with curved edges (Specac model no. GS20522). To keep the path length constant at 0.02 mm, a rectangular polytetrafluoroethylene spacer was used. The mathematical calculations and statistical analyses were done in OriginPro 2019b. Before analysis, the raw NIR data were baseline-corrected. All the mathematical and statistical treatments were performed for the NIR data in the range from 6000 to 7150 cm–1.

Results and Discussion

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The densities and dynamic viscosities of pure [C2mim]C2H5SO4 and propane-1,2-diol were measured along with their binary mixtures over the temperature range from 293.15 to 333.15 K at 5 K intervals. The comparison of the experimental densities and viscosities is tabulated in Table 1.
Table 1. Densities and Dynamic Viscosities of [C2mim]C2H5SO4 and Propane-1,2-diol and Their Comparison with Literature Values at 298.15 K
compoundρ (g cm–3)η (mPa s)
experimentalliteratureexperimentalliterature
[C2mim]C2H5SO41.236171.23635 (33)96.02496.21 (39)
1.23763 (34)97.58 (34)
1.23670 (35)97.2 (40)
propane-1,2-diol1.033331.03262 (36)42.13145.440 (38)
1.03258 (37)43.661 (37)
1.0331 (38)43.437 (41)
Density increases with increasing the mole fraction of [C2mim]C2H5SO4 (Figure 1a). This behavior suggests greater packing in mixtures compared to the pure components and the possibility of the presence of ion–dipole interactions between the unlike molecules. At a lower mole fraction of [C2mim]C2H5SO4, the system behaves like a very dilute ionic solution. As the mole fraction of [C2mim]C2H5SO4 increases, the system gradually becomes a concentrated ionic solution with more or less conspicuous ion pairing. (42,43) The changes in density with temperature for the binary mixtures are depicted in Figure 1b. The density decreases with increasing temperature. The molecular movements (translational, rotational, and vibrational) of [C2mim]C2H5SO4 and propane-1,2-diol molecules increase as the temperature rises. As a result, the volumes of binary mixtures and pure components increase the density decreases.

Figure 1

Figure 1. Variation of density with (a) mole fraction of [C2mim]C2H5SO4 and (b) temperature and variation of viscosity with (c) mole fraction (lines are for visual aids only) and (d) temperature for binary mixtures of [C2mim]C2H5SO4 and propane-1,2-diol. (Lines are predicted from the VFT equation.)

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The dynamic viscosity decreases with increasing mole fraction of [C2mim]C2H5SO4 (Figure 1c) due to the weakening of the coulombic force between the cations and anions of [C2mim]C2H5SO4. When the amount of propane-1,2-diol is higher, the intermolecular hydrogen bonding becomes dominant in the system over the coulombic interaction between ions of [C2mim]C2H5SO4. (44) However, when mole fraction of [C2mim]C2H5SO4 is higher than 0.9, viscosity increases again due to the strong interionic interaction between the cations and anions of [C2mim]C2H5SO4. The change in viscosity with temperature is depicted in Figure 1d. The dynamic viscosity reduces as the temperature rises for each binary system, indicating a slow descent structural relaxation. The temperature dependency of viscosity is more pronounced at lower temperatures. The temperature dependencies of binary mixtures were described by standard models. The two-parameter Arrhenius model, the most widely used model, and of the three-parameter models, the Vogel–Fulcher–Tammann (VFT) (45−47) and modified VFT (mVFT) (48) models were also applied to fit the temperature dependence of dynamic viscosity of the binary mixtures and their pure components. The temperature dependence of dynamic viscosity follows all the three models. The fitting parameters calculated from each equation are tabulated in Table S1 along with their correlation coefficient values (R2).
The excess molar volumes for the binary mixtures are calculated from the following (eq 1):
VmE=∑xiMiρmix−∑i=2nxiMiρi
(1)
The excess molar volumes of the binary mixtures are positive over the whole composition range (Figure 2a). The largest value of the excess molar volume is found at 0.9 [C2mim]C2H5SO4 mole fraction. When [C2mim]C2H5SO4 is added to propane-1,2-diol the intermolecular hydrogen bonds between propane-1,2-diol molecules are broken down thus free volume in the solution increases. Hence, molar volume increases. With temperature, the breaking process of hydrogen bonding is favored hence at higher temperatures, values of excess molar volume become more positive. The data points of excess molar volumes for a binary mixture of [C2mim]C2H5SO4 and propane-1,2-diol were fitted with the RK type polynomial expression (eq 2): (49)
YE=x1x2∑i=0nAi(x1−x2)i
(2)
where YE is the excess properties, n is the polynomial order, and x1 and x2 are the mole fractions of [C2mim]C2H5SO4 and propane-1,2-diol, respectively. A0–An are coefficients of the RK equation calculated by the least-squares type algorithm, which are tabulated in Table S2.

Figure 2

Figure 2. Variation of (a) excess molar volumes, (b) dynamic viscosity deviations, (c) excess molar Gibbs free energy of activation for viscous flow, (d) Gibbs free energy, (e) enthalpy, and (f) entropy of activation for the viscous flow of binary mixtures of [C2mim]C2H5SO4 and propane-1,2-diol as a function of mole fraction of [C2mim]C2H5SO4 at various temperatures.

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The dynamic viscosity deviations are calculated from the following (eq 3):
Δη=ηexperimental−∑xiηi
(3)
The dynamic viscosity deviations (Δη) for the binary mixture of [C2mim]C2H5SO4 and propane-1,2-diol are positive up to 0.3 mole fraction of [C2mim]C2H5SO4 and negative with increasing mole fraction of [C2mim]C2H5SO4 (Figure 2b). When the amount of [C2mim]C2H5SO4 in the mixture is smaller, the intermolecular hydrogen bonds between propane-1,2-diol molecules are more prominent than the intermolecular interaction with unlike molecules. When the temperature is increased, the Δη becomes more positive.
At a mole fraction of [C2mim]C2H5SO4 higher than 0.3, the intermolecular ions of [C2mim]C2H5SO4 become solvated resulting from the simultaneous breaking of homomolecular hydrogen bonds between propane-1,2-diol molecules and the formation of less strong heteromolecular interaction between [C2mim]C2H5SO4 and propane-1,2-diol. Hence, the value of Δη decreases. The Δη becomes more negative with increasing temperature. Because when temperature increases, the intermolecular attraction decreases; hence, Δη also decreases. The data points of Δη are fitted in eq 1. The coefficients of the RK-type expression are tabulated in Table S2.
The excess molar Gibbs free energy for the viscous flow (ΔG*E) of the binary mixtures are calculated from the following (eq 4):
ΔG*E=RT[ln(ηVη2V2)−x1ln(η1V1η2V2)]
(4)
The ΔG*E of the binary mixture of [C2mim]C2H5SO4 and propane-1,2-diol are unsymmetrical and all negative over the whole composition range (Figure 2c). The values of the ΔG*E are more negative at higher [C2mim]C2H5SO4 content because of the smaller number of hydrogen bonds present in the system. (50−52) The data points of ΔG*E are fitted in eq 1. The coefficients of the RK-type expression are tabulated in Table S2. Activation enthalpy (ΔH*) and entropy (ΔS*) for viscous flow were calculated from the Eyring theory using the following (eq 5):
η=hNAVe(ΔH*/RT−ΔS*/R)
(5)
From the values of ΔH* and ΔS*, the activation Gibbs free energy was calculated from the following (eq 6):
ΔG*=ΔH*−TΔS*
(6)
The values of activation parameters for the binary mixture of [C2mim]C2H5SO4 and propane-1,2-diol are summarized in Table S3, respectively, along with R2 values.
The values of ΔG* are all positive over the whole composition range (Figure 2d). The positive values of ΔG* indicate that activation processes for viscous flow are non-spontaneous and molecules absorb energy to perform useful work. The value of ΔG* increases slightly with increasing mole fraction of [C2mim]C2H5SO4 up to 0.85 and the change of ΔG* is very small at a lower mole fraction of [C2mim]C2H5SO4 up to 0.85 and then increases abruptly in the pure component. As discussed earlier, the ΔG* controls fluid flow, which is governed by the ability of the molecules and/or ions to move into a structural hole and the capability to create another hole. The increase in the ΔG* value indicates an increasing amount of intermolecular attraction forces between the unlike molecules. The values of ΔS* are all negative over the whole composition range (Figure 2e). At a lower mole fraction of [C2mim]C2H5SO4, the entropy decreases indicating that the addition of [C2mim]C2H5SO4 in liquid propane-1,2-diol makes the system more ordered. However, at higher mole fractions, the entropy change fluctuates indicating the breaking of the hydrogen bond between propane-1,2-diol and the reformation of the solvation cage depending on the number of ions present in propane-1,2-diol. The binary mixtures with mole fractions 0.4, 0.7, and 0.9 have the lowest values that indicate structures of these mixtures are the most ordered structures. The positive values of ΔH* over the whole composition range at each temperature (Figure 2f) indicate that the mixing of [C2mim]C2H5SO4 in propane-1,2-diol is an endothermic process. The values of ΔH* decrease up to a 0.4 mole fraction of [C2mim]C2H5SO4, and fluctuation of ΔH* occurs with more amount of [C2mim]C2H5SO4. The reason for decreasing the value of ΔH* is that the propane-1,2-diol structure is highly interconnected with the number of intermolecular and intramolecular bonds. However, when [C2mim]C2H5SO4 is added to it, some of the bonds are broken down creating a substantial amount of energy, which lowers the value of ΔH*.
Hence, by considering the above thermodynamic activation parameters, at a lower mole fraction of [C2mim]C2H5SO4 up to 0.4, the intermolecular interactions between the like propane-1,2-diol molecules decrease via intermolecular and intramolecular hydrogen bond breaking along with solvation of [C2mim]C2H5SO4 by propane-1,2-diol molecules. Further, the addition of [C2mim]C2H5SO4 creates the shortage of propane-1,2-diol in the system for solvation to occur, and then there is a competition between intermolecular forces between like molecules of [C2mim]C2H5SO4 and propane-1,2-diol. It is in sharp contrast to [C2mim]C2H5SO4/propane-1-ol binary system, where due to the less number of hydrogen bonding sites the intermolecular hydrogen bonds easily break down and solvate the ions when [C2mim]C2H5SO4 is added to propane-1-ol, hence excess thermodynamic properties are negative, (32) but in case of the [C2mim]C2H5SO4/propane-1,2-diol system, the excess thermodynamic parameters are positive due to the stronger intermolecular association of propane-1,2-diol molecules by forming more hydrogen bonding network.
The NIR spectroscopic measurements were carried out for pure propane-1,2-diol and [C2mim]C2H5SO4 at the temperature range from 293.15 to 333.15 K at a 5 K intervals. The NIR spectra are depicted in Figure 3. In NIR spectra of propane-1,2-diol, numbers of peaks are present in the range between 6000 and 7150 cm–1. The peaks in this region are assigned as peaks of the first overtone band of −OH stretching vibration for −OH bonds in different electronic environments. (53,54)

Figure 3

Figure 3. NIR spectra of (a) pure propane-1,2-diol and (b) [C2mim]C2H5SO4 at temperatures from 293.15 to 313.15 K at 5 K intervals.

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The peak at 7016 cm–1 is assigned to the −OH group, which is hydrogen bond acceptors only and the peak at 7100 cm–1 is for non-hydrogen-bonded free −OH groups. (55) As the temperature increases, the intensity of absorbance for the band at 7050 cm–1 increases, and at a higher temperature, it becomes sharp suggesting that with increasing temperature number of intermolecular hydrogen bonds decreases. Besides, the intensity of peak at 7050 cm–1 also increases with temperature, indicating that at higher temperatures, some of the intermolecular hydrogen bonds break down to form free propane-1,2-diol.
The peaks at 6300 and 6800 cm–1 are for cooperative intermolecular and intramolecular and non-cooperative intermolecular and intramolecular hydrogen-bonded −OH groups, respectively. (46) The decrease in intensity of these bands also suggests the presence of a higher number of hydrogen-bonded −OH groups in the different molecular environments. There exists an isosbestic point at 6720 cm–1. In the NIR spectra of [C2mim]C2H5SO4, there is only one broad peak at 6200 cm–1 that remains unchanged with temperature. This peak comes from the second overtone of −CH stretching.
The temperature-perturbed 2D correlation spectral analysis of propane-1,2-diol in the temperature range 293.15 to 333.15 K from 6000 to 7150 cm–1 was performed for the raw spectral data. Figure 4 shows the synchronous and asynchronous spectra of the 2D correlation analysis of propane-1,2-diol in the region of 6000–7150 cm–1.

Figure 4

Figure 4. (a) Synchronous and (b) asynchronous 2D NIR correlation spectra and loadings and scores (c) PC1 and (d) PC2 calculated from the temperature-dependent spectral changes (293.15 to 313.15 K) of pure propane-1,2-diol.

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The synchronous 2D NIR correlation spectrum shows two major diagonal auto peaks. The auto peak at 6300 cm–1 is for the hydrogen-bonded O-H bond. However, the auto peak at 7016 cm–1 has high correlation intensity (more than 10 times that of the peak at 6300 cm–1). This suggests that in propane-1,2-diol, the intermolecular hydrogen bonds are present but most of the O-H bonds are hydrogen bond acceptors, and also a smaller number of the free hydroxyl groups are present in the propane-1,2-diol system.
The negative cross-peaks between these auto peaks suggest that spectral changes at these positions are negatively correlated to each other. In addition, since the cross-peak of 6300 and 7016 cm–1 in the asynchronous map is negative, the variance at 6300 cm–1 occurs at higher temperatures compared to that at 7016 cm–1. According to the principle of 2D correlation spectra, as the temperature rises, the vibration at 6300 cm–1 transforms into the vibration at 7016 cm–1. To verify and quantify the results of 2D correlation spectra, principal component analysis (PCA) was done for propane-1,2-diol in the same temperature and wavenumber range of the 2D correlation. The PCA of propane-1,2-diol gives nine principal components, then the first two components dominated over 99.94173% of the total system. The other seven components have very little contribution to the total spectra. The eigenvalues and percentage of variance for the principal components of propane-1,2-diol are given in Table 2.
Table 2. Eigenvalues and Percentage of Variance for the Principal Components of Propane-1,2-diol
principal componentseigen valuespercentage of variancecumulative percentage
11.71285 × 10–499.5748299.57482
26.31134 × 10–70.366999.94173
34.71752 × 10–80.0274299.96915
42.38761 × 10–80.0138899.98303
51.33195 × 10–80.0077499.99077
67.45778 × 10–90.0043499.99511
75.39172 × 10–90.0031399.99824
83.01935 × 10–90.00176100
91.16175 × 10–346.75368 × 10–29100
The loading of the PC1 shows a broad peak at 6300 cm–1, with a significant shoulder at 6600 cm–1 (Figure 4c), signifies the presence of a hydrogen-bonded cluster dominated by this principal component. In addition, there is a negative peak at 7016 cm–1 which corresponds to the auto peak and cross-peaks of 2D correlation spectra, respectively. The scores of this principal component decrease with increasing temperature. In the case of PC2 in the hydrogen-bonded region, there is no significant peak rather stronger peaks at 7100 cm–1 and higher wavenumbers (Figure 4d). This signifies PC2 is predominantly non-hydrogen-bonded propane-1,2-diol. The scores of PC2 decrease first and then increase with increasing temperature. As the temperature rises, hydrogen-bonded clusters of propane-1,2-diol begin to break down to form non-hydrogen-bonded free propane-1,2-diol molecules.
The NIR spectra of the prepared binary mixtures were recorded over a temperature range from 293.15 to 333.15 K at a 5 K intervals. For pure propane-1,2-diol, the presence of two broad peaks in the region between 6200 to 7000 cm–1 suggests the presence of different types of clusters in the pure propane-1,2-diol system. (16) However, when [C2mim]C2H5SO4 is added to it, some of the structural modification occurs that reflects in the shifting of the bands and change in their intensities. At 0.1 [C2mim]C2H5SO4 mole fraction, the broad peak at 6200 cm–1 undergoes a blueshift suggesting the weakening of the strength of hydrogen bonds between the molecules. As the peak at 6200 cm–1 is for the doubly hydrogen-bonded species, it can be predicted that one of the two hydrogen bonds weakened due to the effect of [C2mim]C2H5SO4. The redshift of the peak in the region of 6932 cm–1 suggests the strengthening of the intramolecular hydrogen bonding in the propane-1,2-diol molecule. This is due to the fact that when one of the two hydrogen bonds becomes weaker, the other one becomes stronger. As the intermolecular hydrogen bonds become weaker due to the addition of [C2mim]C2H5SO4, the intramolecular bonds become stronger. Another new peak observed in the region of 6800 cm–1 suggests the inclusion of a new type of species containing weak hydrogen bonding interaction. Surprisingly, the peak at 7080 and 7016 cm–1 is absent for the 0.1 [C2mim]C2H5SO4 mole fraction binary system suggesting that the free −OH groups are engaged with any of the hydrogen bonding interaction.
The 2D synchronous contour map shows a strong auto peak at 7016 cm–1 and broader and weaker auto peaks at 6332 and 6594 cm–1, respectively (Figure S1). These auto peaks suggest a strong correlation between the peaks. The off-diagonal negative cross-peaks between 7016 and 6594 cm–1 and between 7016 and 6332 cm–1 suggest that these peaks are negatively correlated with one another. The asynchronous contour map also shows a strong negative correlation between the peak at 7016 cm–1 and the peaks at 6332 and 6594 cm–1 (Figure S1). It is evident that the broad peak at 6932 cm–1 is composed of at least two peaks at 6594 and 7016 cm–1.
For further quantitative analysis, PCA is done for this spectral data (Table S4). The first principal component PC1 contributes to 66.29023% of the total spectral variance and has loadings that are dominated by broad negative peaks between 6200 and 6900 cm–1 and a positive peak at 7016 cm–1, which indicates the presence of negatively correlated peaks in this species (Figure S2). The scores are increasing with increasing temperature. At lower temperature, clusters of PC1 contains more doubly hydrogen-bonded species, and at increasing temperature, this species is partially broken down to form a single hydrogen-bonding-accepting species. The loadings of the second principal component, PC2, which have a 31.69037% contribution to the total spectral variance, show the presence of a single positive peak centering at 7000 cm–1, and the positive scores are found at temperatures 293.15, 303.15, 318.15, and 333.15 K. In other temperatures, the scores are negative. This fluctuation indicates the existence of several temperatures that change the spectral features. The shape of the peak at 7000 cm–1 indicates the presence of two or more peaks inside this. The two shoulders at the left and right side of this peak indicate that there exists some free −OH.
At 0.2 [C2mim]C2H5SO4 mole fraction, the peak at 6184 cm–1 due to the second overtone of the C–H stretching vibration for C–H of the imidazolium ring becomes more intense and separable, but the intensity of the peaks for strongly hydrogen-bonded O–H vibrations becomes less intense. A broad peak at 7000 cm–1 is also found similar to that of 0.1 [C2mim]C2H5SO4 mole fraction. The 2D correlation synchronous contour map of this binary mixture gives strong auto peaks at 7016 and 6320 cm–1 (Figure S3). The negative cross-peaks between these two peaks suggest that these two peaks are negatively correlated to each other. The peak at 6320 cm–1 is divergent to the off-diagonal position suggesting the presence of more bonds inside this region. These more bonds are for different types of hydrogen bonds present in this system. The difference between the spectrum of 0.1 and 0.2 [C2mim]C2H5SO4 mole fraction is in the broadness of the auto peaks. The broader auto peak for the latter system suggests more peak shifting. The PC1 has a variance value of 62.98869% and contains two positive peaks at 6184 and 6520 cm–1 (Table S5). The scores show an almost constant value near zero from temperature 298.15 to 328.15 K, but, at 333.15 K, the scores become negative indicating a sharp spectral variation of PC1 at this temperature (Figure S4). The PC2 for this is the same as PC2 of 0.1[C2mim]C2H5SO4 mole fraction in the mixture. The only difference is in the scores. Whereas the scores for the former mixture were fluctuating, the scores for the latter one increase linearly with temperature. The loadings of PC3 give a negative peak at 6184 cm–1 and a broad positive peak at 6750 cm–1. The scores at 303.15 K temperature show a sharp decrease in the score value. The most interesting feature of all the principal components for this particular binary system is that at 303.15 K there is a sharp change in score.
For [C2mim]C2H5SO4 mole fraction of 0.3 in the mixture, the peak at 6184 cm–1 becomes more resolved and the peak at 6332 cm–1 becomes vanished. This is because when [C2mim]C2H5SO4 is added to propane-1,2-diol, the intermolecular stronger hydrogen bonds are broken down and new weaker hydrogen bonds are formed between unlike molecules. The blueshift of the peaks at 6900 cm–1 gives further evidence of this occurrence. The synchronous 2D correlation contour plot of this binary system has three major auto peaks at 6672 and 7016 cm–1 (Figure S5). Besides these major peaks, there is a minor auto peak at 6184 cm–1. The negative correlations between the peaks at 6672 and 7016 cm–1, 6194, and 6672 cm–1 are confirmed by the presence of negative cross-peaks. The positive cross-peaks between 6184 and 7016 cm–1 show that there is a positive correlation between these peaks. Hence, at 0.3 [C2mim]C2H5SO4 mole fraction, as the temperature increases the hydrogen bonds break down and form weaker hydrogen-bonded species. Positive correlation between the peaks for 6184 and 7016 cm–1 shows that the inclusion of [C2mim]C2H5SO4 in propane-1,2-diol increases the probability of finding clusters with the weakly hydrogen-bonded −OH group. Loadings of PC1 that have a 73.86322% contribution to the total spectral variation give weak positive peaks at 6184 and 7016 cm–1 and negative peaks at 6332 and 6672 cm–1 (Table S6). The scores of PC1 give a sharp increase at 308.15 K and then become mostly unchanged up to 328.15 K (Figure S6). This observation shows that the contribution of PC1 in spectral variation has some significant variation at 308.15 K. The loadings of peaks suggest that PC1 is mainly imidazolium cations solvated with propane-1,2-diol via weak hydrogen bonds and some of the −OH groups are intramolecularly hydrogen-bonded also. The loadings of PC2 have a sharp peak at 6998 cm–1. There are some noises in the hydrogen bonding overtone region. Therefore, the PC2 is mainly the component where majorly propane-1,2-diol are found of which a very small number of weak hydrogen bonds are found.
The NIR spectra of 0.4 [C2mim]C2H5SO4 mole fraction mixture is almost similar to that of 0.3 [C2mim]C2H5SO4 mole fraction. All the peak positions are the same as the former one except small blueshift of the peak at 6900 cm–1. The synchronous 2D correlation contour plot shows nothing below 7000 cm–1. This is because the spectral features are not changed much with temperature. The other features are similar to the former one. The PCA shows that PC1 is responsible for 92.08753% of the total spectral variation. The position of the peaks in the loading of PC1 is similar to that of 0.3 but scores linearly increase here. The PC2 is also similar to the former one.
As the mole fraction of [C2mim]C2H5SO4 increases, the peak at 6184 cm–1 becomes more intense and the peak at 6300 cm–1 diminishes. The reason for the increase in the intensity of the peak at 6184 cm–1 is the increasing number of this particular bond, and the vanishing of the peak at 6300 cm–1 suggests the breaking of the strong multiple hydrogen bonds to form weaker bonds. Another interesting feature of this binary mixture is that as the mole fraction of [C2mim]C2H5SO4 is increased, the position of the auto peak at 7000 cm–1 undergoes blueshift providing evidence of weakening on the intermolecular and intramolecular hydrogen bonds by the addition of [C2mim]C2H5SO4. The 2D synchronous and asynchronous contour plots, and the loadings and scores of the first four components are given in Figures S1–S18, and the eigenvalues and percentage of variance from the PCA are tabulated in Tables S4–S12.
The NIR spectral analysis of the pure propane-1,2-diol shows that in pure propane-1,2-diol intramolecular hydrogen bonding is dominating. Hence, the intermolecular hydrogen bonds are weaker here. However, the number of hydrogen bonds is higher. As the temperature increases, the intermolecular bonds weaken, and the hydrogen bonding structure is disrupted. When [C2mim]C2H5SO4 is added to propane-1,2-diol, the structure of the propane-1,2-diol is broken down. However, due to the domination of intramolecular hydrogen bonds, the molecular voids cannot be filled, increasing in excess molar volume as discussed earlier. At lower content of [C2mim]C2H5SO4, the bonding is stronger resulting in the positive viscosity deviation. The smaller number of bonds between unlike molecules are also predicted in the excess molar Gibbs free energy plot, supported by the NIR spectra. The entropy also decreases with an increasing amount of [C2mim]C2H5SO4. At higher content of [C2mim]C2H5SO4, the intermolecular bonds between propane-1,2-diol molecules become insignificant and the expected amount of hydrogen bonding interaction is not formed due to the intervention from intramolecular bonds as observed from NIR analysis. At higher content of [C2mim]C2H5SO4, the excess molar volume becomes more positive, viscosity deviation becomes more negative, the excess molar Gibbs free energy is more negative, and activation entropy increases slightly due to the same reason. A visualization of the molecular-level interaction binary mixtures of [C2mim]C2H5SO4 and propane-1,2-diol and their pure components are given in Scheme 1.

Scheme 1

Scheme 1. Schematic Diagram of Molecular-Level Interaction of (a) Pure Propane-1,2-diol, (b) Pure [C2mim]C2H5SO4, (c) Binary Mixture of [C2mim]C2H5SO4 and Propane-1,2-diol When Mole Fraction of Propane-1,2-diol is Greater, and (d) Binary Mixture of [C2mim]C2H5SO4 and Propane-1,2-diol When Mole Fraction of [C2mim]C2H5SO4 is Greater
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Conclusions

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In comparison to the pure components, the physicochemical properties of binary mixtures of [C2mim]C2H5SO4 and propane-1,2-diol differ significantly. The densities increase but viscosities decrease as the content of [C2mim]C2H5SO4 is increased in the mixture. The temperature dependence of viscosity follows non-Arrhenius behavior and is fitted well in VFT and mVFT equations. Excess molar volumes are positive but the other excess thermodynamic parameters are found to be negative for higher [C2mim]C2H5SO4 content. The values of Gibbs free energy of activation for viscous flow are all positive over the whole composition range indicating the non-spontaneity of the viscous flow and are increasing as the mole fraction of [C2mim]C2H5SO4 increases. The entropies are negative indicating the more ordered structure after flowing the liquid. The trends of enthalpy change are the same as those of entropy. The NIR spectral analysis shows that as the mole fraction of [C2mim]C2H5SO4 increases the intermolecular bonds between propane-1,2-diol molecules are broken down, some of the -OH groups form the solvated [C2mim]C2H5SO4 cations and anions, and some of the -OH groups become free from intermolecular hydrogen bonds and form intramolecular hydrogen bonds. It is thus the interplay between intermolecular and intramolecular hydrogen bonding that dictates the physicochemical properties of the IL with an alcohol.

Supporting Information

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The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acsomega.3c03457.

  • Fitted parameters (A, B, T0) and corresponding fitting coefficient (R2) of the various equations for the viscosities; coefficients of the Redlich–Kister equation (Ai); activation enthalpy and activation entropy of viscous flow of the binary system of [C2mim]C2H5SO4 and propane 1,2-diol at different temperatures; eigenvalues and percentage of variance for the principal components of the binary mixture of [C2mim]C2H5SO4 and propane-1,2-diol of 0.1001 to 0.8911[C2mim]C2H5SO4 mole fraction; and synchronous and asynchronous 2D NIR correlation spectra calculated from the temperature-dependent spectral changes and loadings and scores for the PC1, PC2, PC3, and PC4 of the temperature-dependent NIR spectra of the binary mixture of [C2mim]C2H5SO4 and propane-1,2-diol at 0.1011–0.8911 [C2mim]C2H5SO4 mole fraction in the range of 6000–7500 cm–1 (PDF)

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Author Information

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  • Corresponding Author
  • Author
    • Md. Ahad Ali - Department of Chemistry, University of Dhaka, Dhaka 1000, Bangladesh;  Department of Chemistry, Jashore University of Science and Technology, Jashore 7408, Bangladesh
  • Notes
    The authors declare no competing financial interest.

Acknowledgments

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The authors acknowledge Dhaka University to provide Article Publishing Charges under the International Publication Grant of Dhaka University. Bose Center for Advanced Study and Research in Natural Sciences is acknowledged for financial support. M.A.A. also acknowledges an NST Fellowship from the Ministry of Science and Technology, Bangladesh.

References

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This article references 55 other publications.

  1. 1
    Freemantle, M. An Introduction to Ionic Liquids; RSC Publishing: Cambridge, UK, 2009.
    Google Scholar
    There is no corresponding record for this reference.
  2. 2
    Angell, C. A.; Ansari, Y.; Zhao, Z. Ionic Liquids: Past, Present and Future. Faraday Discuss. 2012, 154, 9– 27,  DOI: 10.1039/C1FD00112D
    Google Scholar
    2
    Ionic liquids: past, present and future
    Angell C Austen; Ansari Younes; Zhao Zuofeng
    Faraday discussions (2012), 154 (), 9-27; discussion 81-96, 465-71 ISSN:1359-6640.
    An overview of the field of low-melting ionic liquids is given from its inception in 1886 through to the present time. The subject is divided into an introductory section that summarizes the early history of the field, and differentiates its subsections, before addressing matters judged of some interest in "pre-surge" and "post-surge" stages of its development, focusing on physicochemical as opposed to the prolific synthetic and industrial aspects in which the author has no competence. We give a final section specifically to protic ionic liquids, which we consider to have particular scientific potential.
  3. 3
    Stalpaert, M.; Peeters, N.; de Vos, D. Conversion of Lactide to Acrylic Acid by a Phosphonium Ionic Liquid and Acid Cocatalyst. Catal. Sci. Technol. 2018, 8, 1468– 1474,  DOI: 10.1039/C7CY02364B
    Google Scholar
    3
    Conversion of lactide to acrylic acid by a phosphonium ionic liquid and acid cocatalyst
    Stalpaert, M.; Peeters, N.; De Vos, D.
    Catalysis Science & Technology (2018), 8 (5), 1468-1474CODEN: CSTAGD; ISSN:2044-4753. (Royal Society of Chemistry)
    Acrylic acid, an important starting compd. for a wide variety of consumer products, is generally produced through selective oxidn. of propene. A more sustainable approach would be its synthesis from lactic acid, since this compd. is generally produced by fermn. of renewable sugar streams. Up to now, most research on this reaction has involved gas phase reactions, which require high temps., often above 300 °C. Building on our previous work, which demonstrated the ionic liq. tetrabutylphosphonium bromide, combined with an acid cocatalyst, as an interesting catalyst for dehydration and dehydrohalogenation reactions, we here report the use of this catalytic system in the conversion of lactide to acrylic acid. Initial expts. showed the formation of the volatile side products ethylene, bromoethane and acetaldehyde, which could explain mass loss that was not well understood heretofore. A combination of liq. phase GC anal. and gas phase FTIR spectroscopy allowed us to close the mass balance. As a result, a reaction network was proposed and supported by exptl. studies. Finally, the insights in the reaction network were applied to achieve a very good acrylic acid yield of 70%.
  4. 4
    Yan, D.; Wang, G.; Gao, K.; Lu, X.; Xin, J.; Zhang, S. One-pot Synthesis of 2, 5-Furandicarboxylic Acid from Fructose in Ionic Liquids. Ind. Eng. Chem. Res. 2018, 57, 1851– 1858,  DOI: 10.1021/acs.iecr.7b04947
    Google Scholar
    4
    One-Pot Synthesis of 2,5-Furandicarboxylic Acid from Fructose in Ionic Liquids
    Yan, Dongxia; Wang, Gongying; Gao, Kai; Lu, Xingmei; Xin, Jiayu; Zhang, Suojiang
    Industrial & Engineering Chemistry Research (2018), 57 (6), 1851-1858CODEN: IECRED; ISSN:0888-5885. (American Chemical Society)
    2,5-Furandicarboxylic acid (FDCA), which is usually produced from HMF catalyzed by noble metal catalysts, is an important bio-based monomer for the degradable polymer polyethylene furandicarboxylate (PEF). In order to reduce the high costs of starting material and catalysts, a novel approach for the direct conversion of fructose into FDCA was developed by employing [Bmim]Cl as a solvent with non-noble metal (Fe-Zr-O) as a catalyst. Relatively high FDCA yield was obtained at full fructose conversion under optimal conditions. The kinetic study revealed that the oxidn. of intermediate FFCA to FDCA possessed the highest activation energy, indicating this step is most affected by reaction temp. Addnl., in the IL-promoted reaction system, other biomass sources, such as glucose, galactose, mannose, starch and cellulose also can be directly converted, with lower FDCA yield compared with that of fructose due to the ineffective isomerization of aldohexoses into fructose.
  5. 5
    Wei; Wang, Y.; Chen, J.; Xu, P.; Zhou, Y. Preparation of Ionic Liquid Modified Magnetic Metal-Organic Frameworks Composites for The Solid-Phase Extraction of α–Chymotrypsin. Talanta 2018, 182, 484– 491,  DOI: 10.1016/j.talanta.2018.02.022
    Google Scholar
    5
    Preparation of ionic liquid modified magnetic metal-organic frameworks composites for the solid-phase extraction of α-chymotrypsin
    Wei, Xiaoxiao; Wang, Yuzhi; Chen, Jing; Xu, Panli; Zhou, Yigang
    Talanta (2018), 182 (), 484-491CODEN: TLNTA2; ISSN:0039-9140. (Elsevier B.V.)
    A novel magnetic solid-phase extn. (MSPE) method based on 1-hexyl-3-Me imidazolium chloride ionic liq. (IL) modified magnetic Fe3O4 nanoparticles, hydroxylated multiwall carbon nanotubes (MWCNTs-OH) and zeolitic imidazolate frameworks (ZIFs) nanocomposites (Fe3O4-MWCNTs-OH@ZIF-67@IL) were proposed and applied to ext. α-chymotrypsin. The magnetic materials were synthesized successfully and characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), thermal gravimetric anal. (TGA), fourier transform IR spectrometry (FT-IR), vibrating sample magnetometer (VSM) and zeta potentials. Subsequently, the UV-vis spectrophotometer at about 280nm was utilized to quant. analyze the α-chymotrypsin concn. in the supernatant. Furthermore, single factor expts. revealed that the extn. capacity was influenced by initial α-chymotrypsin concn., ionic strength, extn. time, extn. temp. and pH value. The extn. capacity could reach up to about 635mgg-1 under the optimized conditions, absolutely higher than that of extn. for Ovalbumin (OVA), Bovine serum albumin (BSA) and Bovine Hb (BHb). In addn., the regeneration studies showed Fe3O4-MWCNTs-OH@ZIF-67@IL particles could be reused several times and kept a high extn. capacity. Besides, the study of enzymic activity also indicated that the activity of the extd. α-chymotrypsin was well maintained 93% of initial activity. What's more, the proposed method was successfully applied to ext. α-chymotrypsin in porcine pancreas crude ext. with satisfactory results. All of above conclusions highlight the great potential of the proposed Fe3O4-MWCNTs-OH@ZIF-67@IL-MSPE method in the anal. of biomols.
  6. 6
    Bogdanov, M. G.; Svinyarov, I. Efficient Purification of Halide-Based Ionic Liquids using Improved Apparatus for Continuous Liquid-Liquid Extraction. Sep. Purif. Technol. 2018, 196, 57– 60,  DOI: 10.1016/j.seppur.2017.07.039
    Google Scholar
    6
    Efficient purification of halide-based ionic liquids by means of improved apparatus for continuous liquid-liquid extraction
    Bogdanov, Milen G.; Svinyarov, Ivan
    Separation and Purification Technology (2018), 196 (), 57-60CODEN: SPUTFP; ISSN:1383-5866. (Elsevier B.V.)
    The purity level of Ionic liqs. (ILs) is a question of immense importance both from fundamental and applied standpoint. In order to improve the purifn. process of halide-based ILs, the latter being starting materials for the synthesis of a vast no. of other ILs, an app. is constructed for continuous liq.-liq. extn. to be used as a tool for purifn. after the quaternization step. The app. employs the heat of the evapg. solvent to heat up the extn. chamber, thus allowing the liq.-liq. extn. to be conducted at elevated temp. The latter improves the process efficiency due to facilitated mass transfer. The purifn. carried out with this tool proved successful in the removal of impurities such as residual starting compds. (N-methylimidazole and haloalkanes) under mild conditions and was shown to give ILs of high purity for considerably reduced consumption of org. solvent and technol. time.
  7. 7
    Rdzanek, P.; Marszalek, J.; Kaminski, W. Biobutanol Concentration by Pervaporation Using Supported Ionic Liquid Membranes. Sep. Purif. Technol. 2018, 196, 124– 131,  DOI: 10.1016/j.seppur.2017.10.010
    Google Scholar
    7
    Biobutanol concentration by pervaporation using supported ionic liquid membranes
    Rdzanek, P.; Marszalek, J.; Kaminski, W.
    Separation and Purification Technology (2018), 196 (), 124-131CODEN: SPUTFP; ISSN:1383-5866. (Elsevier B.V.)
    ABE fermn. uses anaerobic bacteria to produce acetone, butanol and ethanol from carbohydrates. Nowadays, ethanol is used as a petrol additive but butanol, due to its unique properties, can become a future biofuel. To recover n-butanol from the fermn. broth, pervaporation can be used. However, sepn. performance of pervaporation is limited by the polymeric membrane. This problem can be overcome by using an ionic liq., immobilized in the active layer of the membrane. This paper investigates the performance of supported ionic liq. membranes (SILMs) employed for the pervaporative concn. of n-butanol. In the study, two ionic liqs. (ILs), i.e. trihexyl(tetradecyl)phosphoniumtetracyanoborate (P6,6,6,14tcb) and 1-hexyl-3-methylimidazolium hexafluorophosphate (Im6,1hfp), were used. The ILs were immobilized with the help of polyether block amide (PEBA). To prevent the ionic liqs. from leaching out, addnl. polymeric coating was necessary. For this purpose, an addnl. amt. of PEBA was applied directly on the IL-PEBA layer. The pervaporation process was carried out at 29, 37 and 50°. The aq. feed soln. contained three org. components, i.e. acetone, butanol and ethanol in a 3:6:1 mass ratio. The concn. of butanol in the feed was 1.5, 3 and 5%. It was found that the permeation fluxes as well as selectivity of the SILMs could be influenced by different ILs. The highest permeation flux, equal to 6,5 kg/(M2 h), was obsd. for the membrane without an ionic liq. due to a higher water flux. However, the highest concn. of butanol in the permeate was achieved with the P6,6,6,14tcb membrane and the enrichment factor was found to be 14.93 while the selectivity for butanol in relation to water was equal to 8.34.
  8. 8
    Zhang, L.; Shu, Z.; Yang, N.; Wang, B.; Dou, H.; Zhang, N. Improvement in Antifouling and Separation Performance of PVDF Hybrid Membrane by Incorporation of Room Temperature Ionic Liquids Grafted Halloysite Nanotubes for Oil–Water Separation. J. Appl. Polym. Sci. 2018, 135, 46278,  DOI: 10.1002/app.46278
    Google Scholar
    There is no corresponding record for this reference.
  9. 9
    Wilkes, J. S.; Levisky, J. A.; Wilson, R. A.; Hussey, C. L. Dialkylimidazolium Chloroaluminate Melts: A New Class of Room-Temperature Ionic Liquids for Electrochemistry, Spectroscopy and Synthesis. Inorg. Chem. 1982, 21, 1263– 1264,  DOI: 10.1021/ic00133a078
    Google Scholar
    9
    Dialkylimidazolium chloroaluminate melts: a new class of room-temperature ionic liquids for electrochemistry, spectroscopy and synthesis
    Wilkes, John S.; Levisky, Joseph A.; Wilson, Robert A.; Hussey, Charles L.
    Inorganic Chemistry (1982), 21 (3), 1263-4CODEN: INOCAJ; ISSN:0020-1669.
    I (R = Me, Et, Pr, Bu) were prepd. by reaction of the analogous chlorides with AlCl3. I (R = Et) was superior to previous melts in terms of liquidus temp., electrochem. window, and reactivity with Al. It was similar to alkylpyridinium chloroaluminates in its viscosity, cond., wide range of Lewis acidity, and ability to dissolve org. and inorg. compds.
  10. 10
    Zhao, M.; Zheng, L.; Bai, X.; Li, N.; Yu, L. Fabrication of Silica Nanoparticles and Hollow Spheres Using Ionic Liquid Microemulsion Droplets as Templates. Colloids Surf., A 2009, 346, 229– 236,  DOI: 10.1016/j.colsurfa.2009.06.021
    Google Scholar
    10
    Fabrication of silica nanoparticles and hollow spheres using ionic liquid microemulsion droplets as templates
    Zhao, Mingwei; Zheng, Liqiang; Bai, Xiangtao; Li, Na; Yu, Li
    Colloids and Surfaces, A: Physicochemical and Engineering Aspects (2009), 346 (1-3), 229-236CODEN: CPEAEH; ISSN:0927-7757. (Elsevier B.V.)
    Silica products with 2 different morphologies were prepd. using nonaq. ionic liq. microemulsion droplets as templates. The morphologies of the obtained products were characterized by both TEM and SEM. By adjusting the reaction conditions, ellipsoidal nanoparticles were formed under acidic conditions, while hollow silica spheres were obtained under alk. conditions. The size distribution of hollow silica spheres was narrower than that of the ellipsoidal nanoparticles. The various vibration modes of different functional groups in the silica materials were revealed by FTIR spectroscopy. The two samples were both shown to be amorphous, not cryst. by x-ray diffraction (XRD). A simple diagram of the formation process including the hydrolysis and condensation reactions is given. Furthermore, a probable mechanism for the formation of silica materials under acidic or alk. conditions is presented, which may be helpful for better understanding the different silica materials obtained under different conditions.
  11. 11
    Li, Z.; Zhang, J.; Du, J.; Han, B.; Wang, J. Preparation of Silica Microrods with Nano-Sized Pores in Ionic Liquid Microemulsions. Colloids Surf., A 2006, 286, 117– 120,  DOI: 10.1016/j.colsurfa.2006.03.011
    Google Scholar
    11
    Preparation of silica microrods with nano-sized pores in ionic liquid microemulsions
    Li, Zhonghao; Zhang, Jianling; Du, Jimin; Han, Buxing; Wang, Jiaqiu
    Colloids and Surfaces, A: Physicochemical and Engineering Aspects (2006), 286 (1-3), 117-120CODEN: CPEAEH; ISSN:0927-7757. (Elsevier B.V.)
    The microemulsions with ionic liq. (IL) as continuous phase were used to fabricate silica microrods. Porous silica microrods with nano-sized pores could be prepd. in this new type of microemulsions. The effects of water-to-surfactant molar ratio ( w ) and the adding amt. of tetraethylorthosilicate (TEOS) on the morphologies of the obtained silica were studied. SEM, TEM and electron diffraction (ED) were used to characterize the as-prepd. products.
  12. 12
    Moniruzzaman, M.; Kamiya, N.; Goto, M. Biocatalysis in Water-in-ionic Liquid Microemulsions: A Case Study with Horseradish Peroxidase. Langmuir 2009, 25, 977– 982,  DOI: 10.1021/la803118q
    Google Scholar
    12
    Biocatalysis in Water-in-Ionic Liquid Microemulsions: A Case Study with Horseradish Peroxidase
    Moniruzzaman, M.; Kamiya, N.; Goto, M.
    Langmuir (2009), 25 (2), 977-982CODEN: LANGD5; ISSN:0743-7463. (American Chemical Society)
    In this article we report the first results on the enzymic activity of horseradish peroxidase (HRP) microencapsulated in water-in-ionic liq. (w/IL) microemulsions using pyrogallol as the substrate. Toward this goal, the system used in this study was composed of anionic surfactant AOT (sodium bis(2-ethyl-1-hexyl)sulfosuccinate)/hydrophobic IL [C8mim][Tf2N] (1-octyl-3-Me imidazolium bis(trifluoromethylsulfonyl)amide)/water/1-hexanol. In this system, the catalytic activity of HRP was measured as a function of substrate concns., W (molar ratio of water to surfactant), pH, and 1-hexanol content. The curve of the activity-W profile was found to be hyperbolic for the new microemulsion. The apparent Michaelis-Menten kinetic parameters (kcat and Km) were estd. and compared to those obtained from a conventional microemulsion. Apparently, it was found that HRP-catalyzed oxidn. of pyrogallol by hydrogen peroxide in IL microemulsuions is much more effective than in a conventional AOT/water/isooctane microemulsion. The stability of HRP solubilized in the newly developed w/IL microemulsions was examd., and it was found that HRP retained almost 70% of its initial activity after incubation at 28° for 30 h.
  13. 13
    Pavlidis, I. V.; Gournis, D.; Papadopoulos, G. K.; Stamatis, H. Lipases in Water-in-Ionic Liquid Microemulsions: Structural and Activity Studies. J. Mol. Catal. B 2009, 60, 50– 56,  DOI: 10.1016/j.molcatb.2009.03.007
    Google Scholar
    13
    Lipases in water-in-ionic liquid microemulsions: Structural and activity studies
    Pavlidis, Ioannis V.; Gournis, Dimitrios; Papadopoulos, George K.; Stamatis, Haralambos
    Journal of Molecular Catalysis B: Enzymatic (2009), 60 (1-2), 50-56CODEN: JMCEF8; ISSN:1381-1177. (Elsevier B.V.)
    Water-in-ionic liq. (w/IL) microemulsions formulated with non-ionic surfactants, (Tween 20 or Triton X-100) in 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim]PF6), were used as media for lipase-catalyzed esterification reactions. The catalytic behavior and stability of lipases from Candida rugosa, Chromobacterium viscosum and Thermomyces lanuginosa in these novel microemulsions were investigated and compared to other microheterogeneous media used so far for enzyme-catalyzed reactions. The catalytic behavior of the enzymes depends strongly on the surfactant concn. and the water content. The dependence of the esterification activity of lipases on molar ratio of water to surfactant (wo) follows a bell-shaped profile, presenting a max. at wo ≈ 5. The operational stability of lipases in w/IL microemulsions, esp. at high incubation temp. (50°), was significantly increased compared to that obsd. in other microheterogeneous media. The highest half-life times (>100 h) were obtained in w/IL microemulsions with low water content. Conformational studies via Fourier transform-IR (FT-IR) and CD spectroscopy indicated that lipases entrapped in w/IL microemulsions in most cases retain their native structure or adapt a more rigid structure compared to other microheterogeneous media, which correlated well with the stability results. A simple procedure suitable for ester sepn. and enzyme reuse was developed. T. lanuginosa lipase retained 90% of activity after ten reaction cycles in w/IL microemulsions formulated with Tween 20.
  14. 14
    Zheng, W.; Huang, K.; Wu, Y.; Hu, X. Protic Ionic Liquid as Excellent Shuttle of MDEA for Fast Capture of CO2. AIChE J. 2018, 64, 209– 219,  DOI: 10.1002/aic.15921
    Google Scholar
    14
    Protic ionic liquid as excellent shuttle of MDEA for fast capture of CO2
    Zheng, Wen-Tao; Huang, Kuan; Wu, You-Ting; Hu, Xing-Bang
    AIChE Journal (2018), 64 (1), 209-219CODEN: AICEAC; ISSN:0001-1541. (John Wiley & Sons, Inc.)
    An inexpensive protic ionic liq. (PIL), 3-(dimethylamino)-1-propylamine acetate [DMAPAH][Ac], was examd. as an activator of N-methyldiethanolamine (MDEA) for fast flue gas CO2 absorption. PIL-activated MDEA solns. had excellent absorption rate and capacity (≥2.5 mol/kg) performance. A novel absorption mechanism is proposed to account for this phenomenon; the PIL shuttling role is described in detail. Also, enthalpy change ΔHSOL (-45 to -52 kJ/mol), PIL turnover no., and regeneration efficiency (>92%) were measured. These data showed PIL-mediated MDEA solns. may be used as promising absorbents for fast flue gas CO2 capture. © 2017 American Institute of Chem. Engineers AIChE J, 2017.
  15. 15
    Yang, X.; Song, H.; Wang, J.; Zou, W. Temperature and Composition Dependence of The Density, Viscosity and Refractive Index of Binary Mixtures of a Novel Gemini Ionic Liquid with Acetonitrile. RSC Adv. 2016, 6, 29172– 29181,  DOI: 10.1039/C5RA27934H
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    15
    Temperature and composition dependence of the density, viscosity and refractive index of binary mixtures of a novel gemini ionic liquid with acetonitrile
    Yang, Xuzhao; Song, Hao; Wang, Jun; Zou, Wenyuan
    RSC Advances (2016), 6 (35), 29172-29181CODEN: RSCACL; ISSN:2046-2069. (Royal Society of Chemistry)
    A novel asym. gemini ionic liq., 1-(1-methypiperidinium-1-yl)hexane-(1-pyridinium)bi[bis(trifluoromethanesulfonyl)imide] ([MPiC6Py][NTf2]2) was synthesized and characterized by 1H NMR, 13C NMR and IR. Elemental anal. was performed on a Vario EL III instrument. Densities, viscosities and refractive indexes were measured for the binary mixt. of [MPiC6Py][NTf2]2 with acetonitrile over the entire range of mole fractions at temps. from T = (293.15 to 323.15) K under the atm. pressure of 0.1 MPa. Using the basic exptl. data, the excess molar volumes (VEm), the viscosity deviations (Δη) and the refractive index deviations (ΔnD) for the binary systems were calcd. and correlated to the Redlich-Kister polynomial to est. coeffs. and the std. deviation between the exptl. and calcd. values. The neg. values of VEm and Δη result from strong self-assocn. and weak hydrogen bonding interactions between the mols. of [MPiC6Py][NTf2]2 and acetonitrile. The values of ΔnD are all pos. for the binary mixts. and increase with increasing temp. The enthalpy, entropy and excess Gibbs energy of activation of the viscous flow of the binary mixts. also have been detd. The values of molar refraction and polarizability indicate that the dominant interactions between [MPiC6Py][NTf2]2 and acetonitrile are dipole-dipole mol. interactions. The obtained results are hoped to provide helpful information for the fundamental physicochem. properties of asym. gemini ionic liqs. and their further industrial applications.
  16. 16
    Tokuda, H.; Hayamizu, K.; Ishii, K.; Susan, M. A. B. H.; Watanabe, M. Physicochemical Properties and Structures of Room Temperature Ionic Liquids. 1. Variation of Anionic Species. J. Phys. Chem. B 2004, 108, 16593– 16600,  DOI: 10.1021/jp047480r
    Google Scholar
    16
    Physicochemical Properties and Structures of Room Temperature Ionic Liquids. 1. Variation of Anionic Species
    Tokuda, Hiroyuki; Hayamizu, Kikuko; Ishii, Kunikazu; Susan, Md. Abu Bin Hasan; Watanabe, Masayoshi
    Journal of Physical Chemistry B (2004), 108 (42), 16593-16600CODEN: JPCBFK; ISSN:1520-6106. (American Chemical Society)
    Room-temp. ionic liqs. (RTILs) based on 1-butyl-3-methylimidazolium ([bmim]) with a variety of fluorinated anions were prepd., and the thermal behavior, d., viscosity, self-diffusion coeffs. of the cations and anions, and ionic cond. were measured over a wide temp. range. The temp. dependencies of the self-diffusion coeff., viscosity, ionic cond., and molar cond. have been fitted to the Vogel-Fulcher-Tamman equation, and the best-fit parameters for the self-diffusion coeff., viscosity, ionic cond., and molar cond. have been estd., together with the linear fitting parameters for the d. The self-diffusion coeffs. detd. for the individual ions by pulsed-field-gradient spin-echo NMR method exhibit higher values for the cation compared with the anion over a wide temp. range, even if its radius is larger than that of the anionic radii. The summation of the cationic and anionic diffusion coeffs. for the RTILs follows the order [bmim][(CF3SO2)2N] > [bmim][CF3CO2] > [bmim][CF3SO3] > [bmim][BF4] > [bmim][(C2F5SO2)2N] > [bmim][PF6] at 30 °C, and the order of the diffusion coeffs. greatly contrasts to the viscosity data. The ionic assocn. is proposed from the results of the ratios of molar cond. obtained from impedance measurements to that calcd. by the ionic diffusivity using the Nernst-Einstein equation. The ratio for the ionic liqs. follows the order [bmim][PF6] > [bmim][BF4] > [bmim][(C2F5SO2)2N] > [bmim][(CF3SO2)2N] > [bmim][CF3SO3] > [bmim][CF3CO2] at 30 °C and provides quant. information on the active ions contributing to ionic conduction in the diffusion components.
  17. 17
    Tokuda, H.; Hayamizu, K.; Ishii, K.; Susan, M. A. B. H.; Watanabe, M. Physicochemical Properties and Structures of Room Temperature Ionic Liquids. 2. Variation of Alkyl Chain Length in Imidazolium Cation. J. Phys. Chem. B 2005, 109, 6103– 6110,  DOI: 10.1021/jp044626d
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    17
    Physicochemical Properties and Structures of Room Temperature Ionic Liquids. 2. Variation of Alkyl Chain Length in Imidazolium Cation
    Tokuda, Hiroyuki; Hayamizu, Kikuko; Ishii, Kunikazu; Susan, Md. Abu Bin Hasan; Watanabe, Masayoshi
    Journal of Physical Chemistry B (2005), 109 (13), 6103-6110CODEN: JPCBFK; ISSN:1520-6106. (American Chemical Society)
    The alkyl chain length of 1-alkyl-3-methylimidazolium bis(trifluoromethane sulfonyl)imide ([Rmim][(CF3SO2)2N], R = Me (m), Et (e), Bu (b), hexyl (C6), and octyl (C8)) was varied to prep. a series of room-temp. ionic liqs. (RTILs), and the thermal behavior, d., viscosity, self-diffusion coeffs. of the cation and anion, and ionic cond. were measured over a wide temp. range. The self-diffusion coeff., viscosity, ionic cond., and molar cond. change with temp. following the Vogel-Fulcher-Tamman equation, and the d. shows a linear decrease. The pulsed-field-gradient spin-echo NMR method reveals a higher self-diffusion coeff. for the cation compared to that for the anion over a wide temp. range, even if the cationic radius is larger than that of the anion. The summation of the cationic and anionic diffusion coeffs. for the RTILs follows the order [emim][(CF3SO2)2N] > [mmim][(CF3SO2)2N] > [bmim][(CF3SO2)2N] > [C6mim][(CF3SO2)2N] > [C8mim][(CF3SO2)2N], which greatly contrasts to the viscosity data. The ratio of molar cond. obtained from impedance measurements to that calcd. by the ionic diffusivity using the Nernst-Einstein equation quantifies the active ions contributing to ionic conduction in the diffusion components, in other words, ionicity of the ionic liqs. The ratio decreases with increasing no. of carbon atoms in the alkyl chain. Finally, a balance between the electrostatic and induction forces has been discussed in terms of the main contribution factor in detg. the physicochem. properties.
  18. 18
    Tokuda, H.; Ishii, K.; Susan, M. A. B. H.; Tsuzuki, S.; Hayamizu, K.; Watanabe, M. Physicochemical Properties and Structures of Room Temperature Ionic Liquids. 3. Variation of Cationic Structures. J. Phys. Chem. B 2006, 110, 2833– 2839,  DOI: 10.1021/jp053396f
    Google Scholar
    18
    Physicochemical Properties and Structures of Room-Temperature Ionic Liquids. 3. Variation of Cationic Structures
    Tokuda, Hiroyuki; Ishii, Kunikazu; Susan, Md. Abu Bin Hasan; Tsuzuki, Seiji; Hayamizu, Kikuko; Watanabe, Masayoshi
    Journal of Physical Chemistry B (2006), 110 (6), 2833-2839CODEN: JPCBFK; ISSN:1520-6106. (American Chemical Society)
    A series of room-temp. ionic liqs. (RTILs) were prepd. with different cationic structures, 1-butyl-3-methylimidazolium ([bmim]), 1-butylpyridinium ([bpy]), N-butyl-N-methylpyrrolidinium, ([bmpro]), and N-butyl-N,N,N-trimethylammonium ([(n-C4H9)(CH3)3N]) combined with an anion, bis(trifluoromethane sulfonyl)imide ([(CF3SO2)2N]), and the thermal property, d., self-diffusion coeffs. of the cation and anion, viscosity, and ionic cond. were measured over a wide temp. range. The self-diffusion coeff., viscosity, ionic cond., and molar cond. follow the Vogel-Fulcher-Tamman equation for temp. dependencies, and the best-fit parameters have been estd., together with the linear fitting parameters for the d. The relative cationic and anionic self-diffusion coeffs. for the RTILs, independently detd. by the pulsed-field-gradient spin-echo NMR method, appear to be influenced by the shape of the cationic structure. A definite order of the summation of the cationic and anionic diffusion coeffs. for the RTILs: [bmim][(CF3SO2)2N] > [bpy][(CF3SO2)2N] > [bmpro][(CF3SO2)2N] > [(n-C4H9)(CH3)3N][(CF3SO2)2N], has been obsd., which coincides with the reverse order to the viscosity data. The ratio of molar cond. obtained from the impedance measurements to that calcd. by the ionic diffusivity using the Nernst-Einstein equation quantifies the active ions contributing to ionic conduction in the diffusion components and follows the order: [bmpro][(CF3SO2)2N] > [(n-C4H9)(CH3)3N][(CF3SO2)2N] > [bpy][(CF3SO2)2N] > [bmim][(CF3SO2)2N] at 30 °C.
  19. 19
    Pereiro, B. A.; Rodriguez, A. P. Thermodynamic Properties of Ionic Liquids in Organic Solvents from (293.15 to 303.15) K. J. Chem. Eng. Data 2007, 52, 600– 608,  DOI: 10.1021/je060497d
    Google Scholar
    19
    Thermodynamic Properties of Ionic Liquids in Organic Solvents from (293.15 to 303.15) K
    Pereiro, Ana B.; Rodriguez, Ana
    Journal of Chemical & Engineering Data (2007), 52 (2), 600-608CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
    Densities, speeds of sound, and refractive indexes of the binary mixts. of BMIM PF6 (1-butyl-3-Me imidazolium hexafluorophosphate), HMIM PF6 (1-hexyl-3-methylimidazolium hexafluorophosphate), OMIM PF6 (1-methyl-3-octylimidazolium hexafluorophosphate), and MMIM CH3SO4 (1,3-dimethylimidazolium Me sulfate) with 2-butanone, ethylacetate, and 2-propanol were detd. from (293.15 to 303.15) K. Excess molar volumes, changes of refractive index on mixing, and deviations in isentropic compressibility were calcd. for the above systems. The liq.-liq. equil. data of the binary mixts. ionic liq. + 2-propanol were carried out, and they were compared with the correlated values obtained by means of the NRTL and UNIQUAC equations.
  20. 20
    AlTwaim, M. S.; Al-Jimaz, A. S.; Alkhaldi, K. H. A. E. Liquid Extraction of Toluene from Heptane, Octane or Nonane Using Mixed Ionic Solvents of 1-Ethyl-3- methylimidazolium Methylsulfate and 1-Hexyl-3-methylimidazolium Hexafluorophosphate. J. Chem. Eng. Data 2019, 64, 169– 175,  DOI: 10.1021/acs.jced.8b00669
    Google Scholar
    There is no corresponding record for this reference.
  21. 21
    Garcıa-Miaja, G.; Troncoso, J.; Romanı, L. Excess Enthalpy, Density, And Heat Capacity for Binary Systems of Alkylimidazolium-based Ionic Liquids and Water. J. Chem. Thermodyn. 2009, 41, 161– 166,  DOI: 10.1016/j.jct.2008.10.002
    Google Scholar
    21
    Excess enthalpy, density, and heat capacity for binary systems of alkylimidazolium-based ionic liquids+water
    Garcia-Miaja, Gonzalo; Troncoso, Jacobo; Romani, Luis
    Journal of Chemical Thermodynamics (2009), 41 (2), 161-166CODEN: JCTDAF; ISSN:0021-9614. (Elsevier Ltd.)
    Exptl. measurements of excess molar enthalpy, d., and isobaric molar heat capacity are presented for a set of binary systems ionic liq. + water as a function of temp. at atm. pressure. The studied ionic liqs. are 1-butyl-3-methylpyridinium tetrafluoroborate, 1-ethyl-3-methylimidazolium ethylsulfate, 1-butyl-3-methylimidazolium methylsulfate, 1-butyl-3-methylimidazolium trifluoromethanesulfonate, and 1-ethyl-3-methylimidazolium trifluoromethanesulfonate. Excess molar enthalpy was measured at 303.15 K whereas d. and heat capacity were detd. within the temp. range 293.15 to 318.15 K. From exptl. data, excess molar volume and excess molar isobaric heat capacity were calcd. The anal. of the excess properties reveals important differences between the studied ionic liqs. which can be ascribed to their capability to form hydrogen bonds with water mols.
  22. 22
    Gonzalez, E. J.; Gonzalez, B.; Calvar, N.; Domınguez, A. Physical Properties of Binary Mixtures of the Ionic Liquid 1-Ethyl-3-Methylimidazolium Ethyl Sulfate with Several Alcohols at T = (298.15, 313.15, and 328.15) K and Atmospheric Pressure. J. Chem. Eng. Data 2007, 52, 1641– 1648,  DOI: 10.1021/je700029q
    Google Scholar
    22
    Physical properties of binary mixtures of the ionic liquid 1-ethyl-3-methylimidazolium ethyl sulfate with several alcohols at T = (298.15, 313.15, and 328.15) K and atmospheric pressure
    Gonzalez, Emilio J.; Gonzalez, Begona; Calvar, Noelia; Dominguez, Angeles
    Journal of Chemical & Engineering Data (2007), 52 (5), 1641-1648CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
    In this contribution, dynamic viscosities, densities, and speeds of sound of 1-ethyl-3-methylimidazolium Et sulfate (EMISE) with methanol, 1-propanol, and 2-propanol at T = (298.15, 313.15, and 328.15) K and refractive indexes at T = 298.15 K and at atm. pressure have been measured over the whole compn. range. Excess molar volumes, excess molar isentropic compressibilities, and viscosity deviations for the binary systems from T = 298.15 K to T = 328.15 K and refractive deviations at 298.15 K have been calcd. and were satisfactorily fitted to a Redlich-Kister equation to give the fitting parameters and the root-mean-square deviations.
  23. 23
    Lehmann, J.; Rausch, M. H.; Leipertz, A.; Fröba, A. P. Densities and Excess Molar Volumes for Binary Mixtures of Ionic Liquid 1-Ethyl-3-Methylimidazolium Ethylsulfate with Solvents. J. Chem. Eng. Data 2010, 55, 4068– 4074,  DOI: 10.1021/je1002237
    Google Scholar
    23
    Densities and Excess Molar Volumes for Binary Mixtures of Ionic Liquid 1-Ethyl-3-methylimidazolium Ethylsulfate with Solvents
    Lehmann, Julia; Rausch, Michael H.; Leipertz, Alfred; Froeba, Andreas P.
    Journal of Chemical & Engineering Data (2010), 55 (9), 4068-4074CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
    In this work d. data for binary mixts. of the ionic liq. 1-ethyl-3-methylimidazolium ethylsulfate ([EMIM][EtSO4]) with acetone, acetonitrile, propylene carbonate, dichloromethane, methanol, ethanol, and water are presented. Measurements were performed in dependence on compn. for temps. from (278.15 to 308.15) K using the vibrating-tube method with an expanded relative uncertainty (k = 2) of less than ± 0.02 %. All calcd. excess molar volumes are neg., indicating denser mol. packing than in the pure liqs. The size and the structure of the solvent mols. as well as the nature of interaction between all mixt. components seem to affect the extent of the obsd. compression effect.
  24. 24
    Kiefer, J.; Molina, M. M.; Noack, K. The Peculiar Nature of Molecular Interactions between an Imidazolium Ionic Liquid and Acetone. ChemPhysChem 2012, 13, 1213– 1220,  DOI: 10.1002/cphc.201100845
    Google Scholar
    24
    The Peculiar Nature of Molecular Interactions between an Imidazolium Ionic Liquid and Acetone
    Kiefer, Johannes; Molina, Marta Martinez; Noack, Kristina
    ChemPhysChem (2012), 13 (5), 1213-1220CODEN: CPCHFT; ISSN:1439-4235. (Wiley-VCH Verlag GmbH & Co. KGaA)
    We present novel insights into the mol. interactions between polar solvents and imidazolium ionic liqs. using the example of 1-ethyl-3-methylimidazolium Et sulfate and acetone. Recently published volumetric property data of this particular system have revealed peculiarities which could not be fully explained by steric effects. In order to shed light on the behavior at a mol. level, we apply IR spectroscopy and analyze solvent-induced line shifts as well as the excess IR spectra. From the spectroscopic results a conclusive picture of the site-specific mol. interactions is developed and our explanation is in concert with the volumetric effects. The data suggest the initial formation of trimers in which acetone interacts with existing ion pairs through interactions of the acetone oxygen atom with the imidazolium ring rather than forming directed hydrogen bonds at the CH moieties. With further addn. of acetone, tetramers are formed which significantly weaken the interionic interactions and eventually initiate ion pair dissocn. Once the ions are released, the anion is rapidly satd. with acetone while the cation solvation proceeds more slowly with acetone addn.
  25. 25
    Reddy, M. S.; Thomas, K.; Raju, S. S.; Nayeem, S. M.; Khan, I.; Krishana, K. B. M.; Babu, B. H. Excess Thermodynamic Properties for Binary Mixtures of Ionic Liquid 1-Ethyl-3-methylimidazolium EthylSulfate and 2-Methoxyethanol from T (298.15 to 328.15) K at Atmospheric Pressure. J. Solution Chem. 2016, 45, 675– 701,  DOI: 10.1007/s10953-016-0465-y
    Google Scholar
    25
    Excess Thermodynamic Properties for Binary Mixtures of Ionic Liquid 1-Ethyl-3-methylimidazolium Ethyl Sulfate and 2-Methoxyethanol from T = (298.15 to 328.15) K at Atmospheric Pressure
    Reddy, M. Srinivasa; Raju, K. Thomas S. S.; Nayeem, Sk. Md.; Khan, Imran; Krishana, K. B. M.; Babu, B. Hari
    Journal of Solution Chemistry (2016), 45 (5), 675-701CODEN: JSLCAG; ISSN:0095-9782. (Springer)
    The d. (ρ), speed of sound (u) and refractive index (nD) for pure [Emim][EtSO4], 2-methoxyethanol and their binary mixts. were measured using an Anton Paar vibrating tube d. and sound velocity meter (DSA 5000 M) and automatic refractometer over the whole compn. range as a function of temp. between 298.15 and 328.15 K in steps of 10 K at atm. pressure. Exptl. values were used to calc. the excess values of molar volumes (VEm), partial molar volumes (‾VEm), partial molar volumes at infinite diln. (‾VE,∞m), isentropic compressibility (κES), acoustic impedance (ZE), free length (LEf), speeds of sound (uE), internal pressure (πEi), free vol. (VEf) and deviations in refractive index (Δ.vphi.nD) for the binary mixts. These properties were fitted to a Redlich-Kister type equation to obtain the binary coeffs. and the std. deviations. The neg. values of VEm, κES, LEf,αEp, and VEf and pos. values for ZE, uE,πEi, and Δ.vphi.nD indicate the existence of strong interactions between the components. This was further supported by IR spectroscopy anal.
  26. 26
    Liu, Q.; Ma, L.; Wang, S.; Ni, Z.; Fu, X.; Wang, J.; Zheng, Q. Study on the properties of density, viscosity, excess molar volume, and viscosity deviation of [C2mim][NTf2],[C2mmim][NTf2],[C4mim][NTf2], and [C4mmim][NTf2] with PC binary mixtures. J. Mol. Liq. 2021, 325, 114573  DOI: 10.1016/j.molliq.2020.114573
    Google Scholar
    26
    Study on the properties of density,viscosity ,excess molar volume,and viscosity deviation of [C2mim][NTf2], [C2mmim][NTf2], [C4mim][NTf2],and [C4mmim][NTf2] with PC binary mixtures
    Liu, Qingshan; Ma, Liansheng; Wang, Shuyi; Ni, Zhiying; Fu, Xiaoyi; Wang, Jian; Zheng, Qige
    Journal of Molecular Liquids (2021), 325 (), 114573CODEN: JMLIDT; ISSN:0167-7322. (Elsevier B.V.)
    The imidazolium type ionic liqs. (ILs) 1-alkyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl] imide ([C2 mim][NTf2] and [C4 mim][NTf2]) were synthesized. For comparing, the ILs with introduction of Me group 1-alkyl-2,3-dimethylimidazolium bis[(trifluoromethyl)sulfonyl]imide ([C2 mmim][NTf2] and [C4 mmim][NTf2]) were also prepd. The d. and viscosity of the systems composed of above ILs and propylene carbonate (PC) were detd. The detd. uncertainties are u(ρ) = 0.00010 g ·cm-3 for d. and ur(η) = 0.02 for viscosity, resp. The excess molar volumes, thermal expansion coeffs., viscosity deviations, and a-const. were calcd. According to Redlich-Kister equation, the relationship between excess molar volume, viscosity deviation and mole fraction was fitted. By comparing with the systems of the same ILs in other org. solvents, the above-mentioned properties were discussed and the influence of introduced methylene group and Me group on the above properties was analyzed.
  27. 27
    Fu, X.; Wang, S.; Huang, Y.; Yang, X.; Liu, Q.; Zheng, Q. Densities and apparent molar volumes of diluent solutions of [EmimNTf2],[BmimNTf2], and [BmmimNTf2] in DEGDME and TEGDME. J. Mol. Liq. 2021, 341, 117328  DOI: 10.1016/j.molliq.2021.117328
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    27
    Densities and apparent molar volumes of diluent solutions of [EmimNTf2], [BmimNTf2], and [BmmimNTf2] in DEGDME and TEGDME
    Fu, Xiaoyi; Wang, Shuyi; Huang, Yulu; Yang, Xiaoxi; Liu, Qingshan; Zheng, Qige
    Journal of Molecular Liquids (2021), 341 (), 117328CODEN: JMLIDT; ISSN:0167-7322. (Elsevier B.V.)
    The densities of six diluents with molality of 0.0199 to 0.5070 mol·kg-1 were measured at atm. pressure from 293.15 to 328.15 K. The studied ionic liqs. (ILs) include 1-ethyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide ([Emim][NTf2]), 1-butyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide ([Bmim][NTf2]), and 1-butyl-2,3-dimethylimidazolium bis[(trifluoromethyl)sulfonyl]imide ([Bmmim][NTf2]). The solvents include diethylene glycol di-Me ether (DEGDME) and tetraethylene glycol di-Me ether (TEGDME). The measured densities were applied for calcn. of Vφ/m3A·mol-1 (apparent molar volume) from 293.15 K to 328.15 K. The influence of the introduction of methylene (-CH2-), Me (-CH3) groups, and the structure of solvents on the d., apparent molar volume were discussed in depth. Redlich-Rosenfeld-Meyer (RRM) equation was used to fit Vφ/m3A·mol-1 dependence on the molality of the six studied diluent solns. Two parameter of Vφ0/m3A·mol-1 (infinite diln. apparent molar volume) and Eφ0/m3A·mol-1A·K-1 (limiting apparent molar expansibility) were also been fitted and discussed based on the RRM equation and polynomial equation, resp. Besides, the interactions of ion-ion and ion-solvent were discussed according to the fitted parameters. The structure making or breaking were also discussed for IL in solvent.
  28. 28
    Liu, Q.; Dai, H.; Chi, H.; Shi, K.; Zheng, Q.; Qi, Y. The density and dynamic viscosity for dilute solutions of [Emim][NTf2][Bmim][NTf2], and [Bmmim][NTf2] in ethylene glycol. J. Mol. Liq. 2023, 371, 121080  DOI: 10.1016/j.molliq.2022.121080
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    28
    The density and dynamic viscosity for dilute solutions of [Emim][NTf2] [Bmim][NTf2], and [Bmmim][NTf2] in ethylene glycol
    Liu, Qingshan; Dai, Haoqi; Chi, Hongyun; Shi, Ketian; Zheng, Qige; Qi, Yanxia
    Journal of Molecular Liquids (2023), 371 (), 121080CODEN: JMLIDT; ISSN:0167-7322. (Elsevier B.V.)
    In this paper, three dil. solns. were prepd. and studied for d. and dynamic viscosity measurement at different temp. ranges and molality ranges. The three dil. solns. are imidazolium cation ionic liqs. (ILs) and ethylene glycol (EG). The measured temp. ranges are (293.15-328.15) K for d. and (298.15-328.15) K for dynamic viscosity, resp. The molality ranges of IL in EG are (0.0100-0.5001) mol•kg-1. The ILs cations are 1-ethyl-3-methylimidazolium, 1-buty-3-methylimidazolium, and 1-butyl-2,3-dimethylimidazolium and anion is bis[(trifluoromethyl)sulfonyl]imide. The molality concn. dependence on apparent molar volume was fitted according to the Redlich-Rosenfeld-Meyer (RRM) equation. The obtained fitted values of apparent molar volumes of infinite diln. (V0Φ/m3•mol-1), Sv/m3•mol-3/2•kg1/2, and Bv/m3•mol-2•kg were used for anal. of ion-solvent interaction and ion-ion interaction in soln. The relative viscosities have also been calcd. from the dynamic viscosities at different temps. and substance concns. The relationship between the relative viscosity and substance concn. of dild. soln. has been characterized by the Jones-Dole equation. The fitted parameters of D and F from the Jones-Dole equation were used for the anal. of interaction changing of solute-solute and solute-solvent. The group introduction of -CH2- (methylene) on position 1 and -CH3 (methyl) on position 2 of imidazolium cation have also been discussed for interaction changing in IL and EG solvent soln. Through the anal. of IL microstructure change, the interaction forces were also described and discussed for the studied solns.
  29. 29
    Fernandes, R. L.; Hoga, H. E.; Torres, R. B. Molecular interactions of ionic liquid {n-butylammonium methanoate (N4Met)+ alcohols} at several temperatures: Thermodynamic and spectroscopic properties. J. Chem. Thermodyn. 2020, 148, 106140  DOI: 10.1016/j.jct.2020.106140
    Google Scholar
    29
    Molecular interactions of ionic liquid {n-butylammonium methanoate (N4Met) + alcohols} at several temperatures: Thermodynamic and spectroscopic properties
    Fernandes, Robert Lunkez; Hoga, Heloisa Emi; Torres, Ricardo Belchior
    Journal of Chemical Thermodynamics (2020), 148 (), 106140CODEN: JCTDAF; ISSN:0021-9614. (Elsevier Ltd.)
    New exptl. data for d., speed of sound and viscosity for binary mixts. of protic ionic liq. {n-butylammonium methanoate (N4Met) + ethanol, or +1-propanol, or +1-butanol, or +1-pentanol} were measured in the whole concn. range at different temps. T = (293.15-313.15) K and p = 92.3 kPa. These results were used to obtain derived mixts. and excess properties. Correlation for viscosity proposed by Grunberg-Nissan, Heric-Brewer, Van der Wyk and Katti-Chaudhri have been used to correlate the viscosity values for the binary mixts. To complement the thermodn. results, spectroscopic studies (1H NMR, 13C NMR, FTIR) have been performed.
  30. 30
    Hoga, H. E.; Fernandes, R. L.; Olivieri, G. V.; Torres, R. B. Molecular interactions of (ionic liquid butylammonium methanoate+ alcohols) at several temperatures. Part II: sec-Butylammonium methanoate (S4Met). J. Chem. Thermodyn. 2023, 178, 106970  DOI: 10.1016/j.jct.2022.106970
    Google Scholar
    There is no corresponding record for this reference.
  31. 31
    Masilo, K.; Bahadur, I. Intermolecular Interactions between 1-Ethyl-3-methylimidazolium-Based Ionic Liquids with Carboxylic Acid at Different Temperatures via Thermodynamic and Spectroscopic Studies. J. Chem. Eng. Data 2021, 66, 1211– 1230,  DOI: 10.1021/acs.jced.0c00728
    Google Scholar
    31
    Intermolecular Interactions between 1-Ethyl-3-methylimidazolium-Based Ionic Liquids with Carboxylic Acid at Different Temperatures via Thermodynamic and Spectroscopic Studies
    Masilo, Kgomotso; Bahadur, Indra
    Journal of Chemical & Engineering Data (2021), 66 (3), 1211-1230CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
    We studied the intermol. interactions of binary mixts. of 1-ethyl-3-methylimidazolium-based ionic liqs. (ILs) with acetic or propionic acid. The physicochem. behavior of the binary mixts. was investigated by measuring the thermophys. properties, including the d. (ρ), sound velocity (u), and refractive index (nD), over the complete range of the IL mole fraction at T = 293.15-333.15 K and p = 0.1 MPa. The surface tension (γ) of the binary mixts. was also measured at T = 298.15 K but not detd. under other studied temps. due to the lack of a temp. controller. The excess molar volumes (VmE), excess isentropic compressibilities (ksE), excess sound velocity (uE), intermol. free length (Lf), deviation in the refractive index (ΔnD), and deviation in the surface tension (Δγ) were detd. from exptl. results. These parameters were further fitted to the Redlich-Kister polynomial equation. FTIR studies of pure components and binary systems at an equimolar compn. were conducted to clarify results from thermodn. properties and also analyze the intermol. interactions occurring in the mixt. A survey on available literature data was carried out to compare with our exptl. data. The selected ILs allowed us to compare the influence of the anion on the thermophys. and thermodn. properties the mixts.
  32. 32
    Ali, M. A.; Susan, M. A. B. H. Volumetric and Spectroscopic Studies of 1-ethyl-3-methylimidazolium Ethylsulfate/Propane-1-ol Binary Mixtures at Different Temperatures. Spectr. Emerg. Sci. 2022, 2, 17– 28,  DOI: 10.55878/SES2022-2-2-5
    Google Scholar
    There is no corresponding record for this reference.
  33. 33
    Hofman, T.; Gołdon, A.; Nevines, A.; Letcher, T. M. Densities, excess volumes, isobaric expansivity, and isothermal compressibility of the (1-ethyl-3-methylimidazolium ethylsulfate+ methanol) system at temperatures (283.15 to 333.15) K and pressures from (0.1 to 35) MPa. J. Chem. Thermodyn. 2008, 40, 580– 591,  DOI: 10.1016/j.jct.2007.11.011
    Google Scholar
    33
    Densities, excess volumes, isobaric expansivity, and isothermal compressibility of the (1-ethyl-3-methylimidazolium ethylsulfate + methanol) system at temperatures (283.15 to 333.15)K and pressures from (0.1 to 35)MPa
    Hofman, Tadeusz; Goldon, Andrzej; Nevines, Ashley; Letcher, Trevor M.
    Journal of Chemical Thermodynamics (2008), 40 (4), 580-591CODEN: JCTDAF; ISSN:0021-9614. (Elsevier Ltd.)
    Densities of pure 1-ethyl-3-methylimidazolium ethylsulfate ionic liq. - [C2mim][EtSO4] and its mixts. with methanol were measured with an accuracy of ±0.2 kg m-3, over the temp. range 283.15-333.15 K and pressure range 0.1-35 MPa, using a vibrating tube densimeter. Excess vols. were calcd. directly from the exptl. densities. The latter data were correlated by the Tait equation with the temp. dependent parameters for the pure ionic liq. and by a van Laar-type equation, involving parameters dependent on temp. and pressure for the mixts. The isobaric expansivity, isothermal compressibility, and related excess properties were calcd. The exceptionally strong influence of pressure and temp. on these properties was obsd.
  34. 34
    Gómez, E.; González, B.; Calvar, N.; Tojo, E.; Domínguez, Á. Physical properties of pure 1-ethyl-3-methylimidazolium ethylsulfate and its binary mixtures with ethanol and water at several temperatures. J. Chem. Eng. Data 2006, 51, 2096– 2102,  DOI: 10.1021/je060228n
    Google Scholar
    34
    Physical properties of pure 1-ethyl-3-methylimidazolium ethylsulfate and Its binary mixtures with ethanol and water at several temperatures
    Gomez, Elena; Gonzalez, Begona; Calvar, Noelia; Tojo, Emilia; Dominguez, Angeles
    Journal of Chemical & Engineering Data (2006), 51 (6), 2096-2102CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
    This paper reports on the synthesis and the phys. properties of the ionic liq. 1-ethyl-3-methylimidazolium ethylsulfate (EMISE). Exptl. densities, speeds of sound and refractive indexes were detd. from (288.15 to 343.15) K. Dynamic viscosities were measured from (298.15 to 343.15) K and surface tension were measured from (288.15 to 313.15) K for pure ionic liq. Densities, dynamic viscosities, speeds of sound, and isentropic compressibilities have been detd. over the whole compn. range for ethanol (1) + EMISE (2) and water (1) + EMISE (2) binary systems at T = (298.15, 313.15, and 328.15) K and atm. pressure. Excess molar volumes, viscosity deviations, and deviations in isentropic compressibility for the binary systems were fitted to a Redlich-Kister equation to det. the fitting parameters and the root mean square deviations. Refractive indexes were measured at 298.15 K over the whole compn. range for the ethanol (1) + EMISE (2) and water (1) + EMISE (2) binary systems. The results were used to calc. deviations in the refractive index.
  35. 35
    Fröba, A. P.; Kremer, H.; Leipertz, A. Density, refractive index, interfacial tension, and viscosity of ionic liquids [EMIM][EtSO4],[EMIM][NTf2],[EMIM][N(CN)2], and [OMA][NTf2] in dependence on temperature at atmospheric pressure. J. Phys. Chem. B 2008, 112, 12420– 12430,  DOI: 10.1021/jp804319a
    Google Scholar
    35
    Density, refractive index, interfacial tension, and viscosity of ionic liquids [EMIM][EtSO4], [EMIM][NTf2], [EMIM][N(CN)2], and [OMA][NTf2] in dependence on temperature at atmospheric pressure
    Froba Andreas P; Kremer Heiko; Leipertz Alfred
    The journal of physical chemistry. B (2008), 112 (39), 12420-30 ISSN:1520-6106.
    The density, refractive index, interfacial tension, and viscosity of ionic liquids (ILs) [EMIM][EtSO 4] (1-ethyl-3-methylimidazolium ethylsulfate), [EMIM][NTf 2] (1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide), [EMIM][N(CN) 2] (1-ethyl-3-methylimidazolium dicyanimide), and [OMA][NTf 2] (trioctylmethylammonium bis(trifluoromethylsulfonyl)imide) were studied in dependence on temperature at atmospheric pressure both by conventional techniques and by surface light scattering (SLS). A vibrating tube densimeter was used for the measurement of density at temperatures from (273.15 to 363.15) K and the results have an expanded uncertainty ( k = 2) of +/-0.02%. Using an Abbe refractometer, the refractive index was measured for temperatures between (283.15 and 313.15) K with an expanded uncertainty ( k = 2) of about +/-0.0005. The interfacial tension was obtained from the pendant drop technique at a temperature of 293.15 K with an expanded uncertainty ( k = 2) of +/-1%. For higher and lower temperatures, the interfacial tension was estimated by an adequate prediction scheme based on the datum at 293.15 K and the temperature dependence of density. For the ILs studied within this work, at a first order approximation, the quantity directly accessible by the SLS technique was the ratio of surface tension to dynamic viscosity. By combining the experimental results of the SLS technique with density and interfacial tension from conventional techniques, the dynamic viscosity could be obtained for temperatures between (273.15 and 333.15) K with an estimated expanded uncertainty ( k = 2) of less than +/-3%. The measured density, refractive index, and viscosity are represented by interpolating expressions with differences between the experimental and calculated values that are comparable with but always smaller than the expanded uncertainties ( k = 2). Besides a comparison with the literature, the influence of structural variations on the thermophysical properties of the ILs is discussed in detail. The viscosities mostly agree with values reported in the literature within the combined estimated expanded uncertainties ( k = 2) of the measurements while our density and interfacial tension data differ by more than +/-1% and +/-5%.
  36. 36
    Zarei, H.; Golroudbari, S. A.; Behroozi, M. Experimental studies on volumetric and viscometric properties of binary and ternary mixtures of N, N-dimethylacetamide, N-methylformamide and propane-1, 2-diol at different temperatures. J. Mol. Liq. 2013, 187, 260– 265,  DOI: 10.1016/j.molliq.2013.07.002
    Google Scholar
    36
    Experimenta5l studies on volumetric and viscometric properties of binary and ternary mixtures of N,N-dimethylacetamide, N-methylformamide and propane-1,2-diol at different temperatures
    Zarei, Hosseinali; Golroudbari, Sajad Akbari; Behroozi, Mahboobe
    Journal of Molecular Liquids (2013), 187 (), 260-265CODEN: JMLIDT; ISSN:0167-7322. (Elsevier B.V.)
    32569748K Excess molar volumes VmE, and viscosity η, of the ternary mixt. of N,N-dimethylacetamide (1) + N-methylformamide (2) + propane-1,2-diol (3) and their binary mixts. were obtained from d. ρ, and viscosity η, measurements over the entire mole fraction range at temps. (293.15 to 333.15) K. Neg. trend were obsd. for the VmE values of the binary mixts. in the whole compn. range except for N-methylformamide (2) + propane-1,2-diol (3) mixt. in the N-methylformamide rich region. Also, neg. VmE values were obsd. for the ternary mixt. except a few mole fractions in accordance with their binary mixts. Effect of rising temp. on the trend of the VmE values is not the same for the mixts. The viscosity values of the mixts. over the entire mole fraction range decrease with increasing temp. The results were interpreted based on the strength of specific interaction, size and shape of mols. The exptl. data of excess molar volumes were correlated with the Redlich-Kister and the Cibulka equations for the binary and ternary mixts., resp.
  37. 37
    Cano-Gómez, J. J.; Iglesias-Silva, G. A.; Cortez-Sánchez, L. D.; Castillo-Escobedo, M. T. Densities and Viscosities for Binary Liquid Mixtures of Butan-1-ol+ Propane-1, 2-diol + Butane-1, 2-diol and 2-Methylpropan-1-ol+ Propane-1, 2-diol,+ Butane-1, 2-diol from 298.15 to 333.15 K at 0.1 MPa. J. Chem. Eng. Data 2017, 62, 4252– 4265,  DOI: 10.1021/acs.jced.7b00621
    Google Scholar
    37
    Densities and Viscosities for Binary Liquid Mixtures of Butan-1-ol + Propane-1,2-diol, + Butane-1,2-diol and 2-Methylpropan-1-ol + Propane-1,2-diol, + Butane-1,2-diol from 298.15 to 333.15 K at 0.1 MPa
    Cano-Gomez, Jose J.; Iglesias-Silva, Gustavo A.; Cortez-Sanchez, Luis D.; Castillo-Escobedo, Maria T.
    Journal of Chemical & Engineering Data (2017), 62 (12), 4252-4265CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
    This paper presents densities and viscosities of binary mixts. of butan-1-ol (or 2-methylpropan-1-ol) with propane-1,2-diol, and butane-1,2-diol from 298.15 to 333.15 K at 0.1 MPa over the entire concn. range. A vibrating tube densimeter provides the densities while a glass capillary viscometer provides the efflux time which is related with the kinematic viscosity. Exptl. densities and viscosities of the pure components agree with data reported in the literature within an av. abs. percentage deviation of 0.03% and 1.16%, resp. The excess molar volumes and viscosity deviation calcd. from exptl. data present neg. deviations from ideality in the entire temp. range. The Redlich-Kister equation is used to represent the compn. behavior of excess molar volumes and the viscosity deviations. The Nava-Rios equation correlates our kinematic viscosity data within an overall av. abs. percentage deviation of 1.085% while the McAllister equation correlates the kinematic viscosity within 1.541%.
  38. 38
    Doghaei, A. V.; Rostami, A. A.; Omrani, A. Densities, viscosities, and volumetric properties of binary mixtures of 1, 2-propanediol+ 1-heptanol or 1-hexanol and 1, 2-ethanediol+ 2-butanol or 2-propanol at T=(298.15, 303.15, and 308.15) K. J. Chem. Eng. Data 2010, 55, 2894– 2899,  DOI: 10.1021/je900954y
    Google Scholar
    38
    Densities, Viscosities, and Volumetric Properties of Binary Mixtures of 1,2-Propanediol + 1-Heptanol or 1-Hexanol and 1,2-Ethanediol + 2-Butanol or 2-Propanol at T = (298.15, 303.15, and 308.15) K
    Doghaei, Asma Verdian; Rostami, Abbas A.; Omrani, Abdollah
    Journal of Chemical & Engineering Data (2010), 55 (8), 2894-2899CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
    Densities and viscosities for 1,2-propanediol + 1-heptanol or 1-hexanol and 1,2-ethanediol + 2-butanol or 2-propanol were measured over the whole compn. range at (298.15, 303.15, and 308.15) K and at atm. pressure. From the exptl. data, the excess molar volume, VmE, partial molar volumes, ‾Vm,1 and ‾Vm,2, and excess partial molar volumes, ‾Vm,1E and ‾Vm,2E, over the entire range of compn. were calcd. Viscosity deviations, Δη, were also obtained and showed neg. values for all investigated systems. These results were fitted to the Redlich-Kister polynomial equation to est. the binary interaction parameters. The viscosity data were correlated with equations of McAllister, and calcd. functions were used to explain the intermol. interaction between the mixing components.
  39. 39
    Anwar, N.; Riyazuddeen Effect of composition and temperature variations on thermophysical properties of binary and ternary mixtures of 1-ethyl-3-methylimidazolium ethylsulfate with 1-butanol and/or methanol. Fluid Phase Equilib. 2017, 437, 127– 139,  DOI: 10.1016/j.fluid.2017.01.019
    Google Scholar
    39
    Effect of composition and temperature variations on thermophysical properties of binary and ternary mixtures of 1-ethyl-3-methylimidazolium ethylsulfate with 1-butanol and/or methanol
    Anwar, Naushad; Riyazuddeen
    Fluid Phase Equilibria (2017), 437 (), 127-139CODEN: FPEQDT; ISSN:0378-3812. (Elsevier B.V.)
    The thermophys. properties, densities, ρ, speeds of sound, u and dynamic viscosities, η of pure ionic liq., 1-ethyl-3-methylimidazolium ethylsulfate, ([EMIM][ES]), and solvents 1-butanol, methanol and of their binary and ternary mixts. have been measured exptl. at a temp. range from (298.15-323.15) K, with an interval of 5 K and at pressure 0.1 MPa by using Anton Paar vibrating tube d. and sound velocity meter DSA 5000M and Lovis microviscometer 2000M. The excess molar volumes, VE, isentropic compressibilities, κs, molar isentropic compressibilities, Ks,m, excess molar isentropic compressibility, KEs,m, and viscosity deviations Δη have been calcd. using the exptl. ρ, u and η data at the same temp. range and pressure for [EMIM][ES] + 1-butanol/methanol binary systems and the VE, κs, excess isentropic compressibility, κEs and Δη for ternary [EMIM][ES] + 1-butanol + methanol system. The VE, κEs, KEs,m and Δη data for the studied binary/ternary systems have been fitted to Redlich-Kister equation. The variations in VE,κEs, KEs,m and Δη values with changes in compn. and temp. have been discussed in terms of hydrogen bonding, ion-dipole interactions and structural effects on mixing of ILs and solvents.
  40. 40
    Arce, A.; Rodil, E.; Soto, A. Volumetric and viscosity study for the mixtures of 2-ethoxy-2-methylpropane, ethanol, and 1-ethyl-3-methylimidazolium ethyl sulfate ionic liquid. J. Chem. Eng. Data 2006, 51, 1453– 1457,  DOI: 10.1021/je060126x
    Google Scholar
    40
    Volumetric and viscosity study for the mixtures of 2-ethoxy-2-methylpropane, ethanol, and 1-ethyl-3-methylimidazolium ethyl sulfate ionic liquid
    Arce, Alberto; Rodil, Eva; Soto, Ana
    Journal of Chemical & Engineering Data (2006), 51 (4), 1453-1457CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
    Densities, viscosities, refractive indexes, and speeds of sound at the temp. of 298.15 K and atm. pressure are reported for the binary and the miscible ternary mixts. of 2-ethoxy-2-methylpropane, ethanol, and 1-ethyl-3-methylimidazolium Et sulfate ionic liq. Excess molar volumes and viscosity, molar refraction, and isentropic compressibility changes of mixing have been calcd. from the phys. properties. The changes of mixing have been adequately fitted to the Redlich-Kister polynomial.
  41. 41
    Živković, E.; Kijevčanin, M.; Radović, I.; Šerbanović, S. P. Viscosities and refractive indices of binary systems acetone+ 1-propanol, acetone+ 1, 2-propanediol and acetone+ 1, 3-propanediol. Chem. Ind. Chem. Eng. Quart. 2014, 20, 441– 455,  DOI: 10.2298/CICEQ130305026Z
    Google Scholar
    41
    Viscosities and refractive indices of binary systems acetone + 1-propanol, acetone + 1,2-propanediol and acetone + 1,3-propanediol
    Zivkovic, Emila M.; Kijevcanin, Mirjana Lj.; Radovic, Ivona R.; Serbanovic, Slobodan P.
    Chemical Industry & Chemical Engineering Quarterly (2014), 20 (3), 441-455CODEN: CICEC2; ISSN:1451-9372. (Association of Chemical Engineers)
    Viscosities and refractive indexes of three binary systems, acetone + 1-propanol, acetone + 1,2-propanediol and acetone + 1,3-propanediol, were measured at eight temps. (288.15, 293.15, 298.15, 303.15, 308.15, 313.15, 318.15 and 323.15 K) and at atm. pressure. From these data, viscosity deviations and deviations in refractive index were calcd. and fitted to the Redlich-Kister equation. The viscosity modeling was done by two types of models: predictive UNIFAC-VISCO and ASOG VISCO and correlative Teja-Rice and McAlister equations. The refractive indexes of binary mixts. were predicted by various mixing rules and compared with exptl. data.
  42. 42
    Zafarani-Moattar, M. T.; Shekaari, H. Volumetric and Speed of Sound of Ionic Liquid, 1-butyl-3-methylimidazolium Hexafluorophosphate with Acetonitrile and Methanol at T = (298.15 to 318.15) K. J. Chem. Eng. Data 2005, 50, 1694– 1699,  DOI: 10.1021/je050165t
    Google Scholar
    42
    Volumetric and speed of sound of ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate with acetonitrile and methanol at T = (298.15 to 318.15) K
    Zafarani-Moattar, Mohammed Taghi; Shekaari, Hemayat
    Journal of Chemical and Engineering Data (2005), 50 (5), 1694-1699CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
    The authors report the d. (ρ) and speed of sound (u) data for 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) + methanol and ([BMIM][PF6]) + acetonitrile binary mixts. over the entire range of their compns. at T = (298.15 to 318.15) K. From these data, excess molar volume and isentropic compressibility deviation values have been calcd. and fitted to the fourth-order Redlich-Kister equation. The excess molar volume values (VE) for acetonitrile mixts. are more neg. than methanol mixts. Isentropic compressibility deviation values (Δκs) in methanol mixts. are more than acetonitrile mixts. The results have been interpreted in terms of ion-dipole interactions and structural factors of the ionic liq. and these org. solvents.
  43. 43
    Wang, J.; Tian, Y.; Zhao, Y.; Zhuo, K. A Volumetric and Viscosity Study for the Mixtures of 1-N-Butyl-3-Methylimidazolium Tetrafluoroborate Ionic Liquid with Acetonitrile, Dichloromethane, 2-Butanone And N N-Dimethylformamide. Green Chem. 2003, 5, 618– 622,  DOI: 10.1039/b303735e
    Google Scholar
    43
    A volumetric and viscosity study for the mixtures of 1-n-butyl-3-methylimidazolium tetrafluoroborate ionic liquid with acetonitrile, dichloromethane, 2-butanone and N, N - dimethylformamide
    Wang, Jianji; Tian, Yong; Zhao, Yang; Zhuo, Kelei
    Green Chemistry (2003), 5 (5), 618-622CODEN: GRCHFJ; ISSN:1463-9262. (Royal Society of Chemistry)
    The densities and viscosities for mixts. of 1-n-butyl-3-methylimidazolium tetrafluoroborate ionic liq. with acetonitrile, dichloromethane, 2-butanone and DMF have been detd. at 298.15 K. From these measurements, it was found that viscosities of the mixts. can generally be described by an exponential equation. Their densities are linear functions of the mass fraction of the ionic liq. in the mixts. These phys. properties can be predicted as a function of the concn. of ionic liq. provided that the properties for pure components are known. The excess molar volume VEm and the excess logarithm viscosities (ln η)E were calcd. and fitted to the Redlich-Kister polynomials. It is shown that the values of VEm are neg. but those of (ln η)E are pos. Surprisingly, the min. in VEm and the max. in (ln η)E are obsd. at about the same mole fraction of the ionic liq., x ≈ 0.3. The results are discussed in terms of the ion-dipole interactions between the cations of the ionic liq. and the org. solutes.
  44. 44
    González, E. J.; Alonso, L.; Domínguez, Á. Physical Properties of Binary Mixtures of the Ionic Liquid 1-Methyl-3-octylimidazolium Chloride with Methanol, Ethanol, and 1-Propanol at T = (298.15, 313.15, and 328.15) K and at P = 0.1 MPa. J. Chem. Eng. Data 2006, 51, 1446– 1452,  DOI: 10.1021/je060123k
    Google Scholar
    44
    Physical properties of binary mixtures of the ionic liquid 1-methyl-3-octylimidazolium chloride with methanol, ethanol, and 1-propanol at T = (298.15, 313.15, and 328.15) K and at P = 0.1 MPa
    Gonzalez, Emilio J.; Alonso, Luisa; Dominguez, Angeles
    Journal of Chemical & Engineering Data (2006), 51 (4), 1446-1452CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
    In this work, dynamic viscosities, densities, and speed of sound of 1-methyl-3-octylimidazolium chloride, [C8mim][Cl], with methanol, ethanol, and 1-propanol at T = (298.15, 313.15, and 328.15) K and refractive index at 298.15 K and 0.1 MPa have been measured over the whole compn. range. Excess molar volumes, isentropic compressibility deviations, and viscosity deviations for the binary systems from T = (298.15 to 328.15) K were calcd. These results were fitted to a Redlich-Kister equation to det. the fitting parameters and the root mean square deviations. As the ionic liq. has a negligible vapor pressure, its recovering from the title mixts. was realized by removal of the alc. component by vacuum at 343.15 K. Appreciable changes in the physicochem. properties of the recovered liq. were not obsd.
  45. 45
    Vogel, D. H. Das Temperatur-abhaengigkeitsgesetz der Viskositaet von Fluessigkeiten. Phys. Z. 1921, 22, 645
    Google Scholar
    45
    The law of the relation between the viscosity of liquids and the temperature
    Vogel, Hans
    Physikalische Zeitschrift (1921), 22 (), 645-6CODEN: PHZTAO; ISSN:0369-982X.
    The formula η1= η∞t-t1/t-t∞ is proposed, where ηt is the viscosity at any temp., t η∞ is the viscosity at another temp., t ∞, and tI is the temp. at which the viscosity is unity. It is said to give excellent agreement with all liquids, including water, mercury, and oils. Since only 3 detns. are required to obtain the consts. it is thought that the formula will be useful in oil technology.
  46. 46
    Fulcher, G. S. Analysis of Recent Measurements of the Viscosity of Glasses. J. Am. Ceram. Soc. 1925, 8, 339– 355,  DOI: 10.1111/j.1151-2916.1925.tb16731.x
    Google Scholar
    46
    Analysis of recent measurements of the viscosity of glasses
    Fulcher, G. S.
    Journal of the American Ceramic Society (1925), 8 (), 339-55CODEN: JACTAW; ISSN:0002-7820.
    If the abs. values of log10 viscosity obtained by Washburn, Shelton and Libman are brought into agreement with those of English the isothermal curves of log10 viscosity as a function of Na2O show no inflection up to 50% Na2O and may be represented by the equation: log10 η = -A + B × 105/(T - T0), where all 3 consts. vary with the compn. When CaO, MgO and Al2O3 are each substituted for Na2O in 6SiO2.2Na2O glasses there is a sharp bend in the curves between 840° and 1050°, designated aggregation temp. at which point the change of log10η per percent is a min., being 0.03-0.06 for CaO, 0.12 for MgO, 0.07 for Al2O3. The sharp bends suggest mol. aggregation but cannot be due to devitrification since it is not a function of time. The curves for the change of log10η in 4SiO2.2Na2O glasses are more complex when B2O3 is substituted for SiO2 than when substituted for Na2O.
  47. 47
    Tammann, G.; Hesse, W. Die Abhängigkeit der Viscosität von der Temperatur bie unterkühlten Flüssigkeiten. Z. Anorg. Allg. Chem. 1926, 156, 245– 257,  DOI: 10.1002/zaac.19261560121
    Google Scholar
    47
    The dependence of viscosity upon the temperature of supercooled liquids
    Tammann, G.; Hesse, W.
    Zeitschrift fuer Anorganische und Allgemeine Chemie (1926), 156 (), 245-57CODEN: ZAACAB; ISSN:0044-2313.
    The authors have measured the viscosity on supercooled liquids whose m. ps. ranged from-114° to +268°. The values of the viscosity η have been plotted against the temp. for each substance chosen. For the temp. interval chosen the curve is hyperbolic. The higher the m. p. the larger is the temp. range through which the viscosity values are found.
  48. 48
    Mauro, J. C.; Yueb, Y.; Ellisona, A. J.; Guptac, P. K.; Allana, D. C. Viscosity of Glass-Forming Liquids. Proc. Natl. Acad. Sci. U. S. A. 2009, 106, 19780– 19784,  DOI: 10.1073/pnas.0911705106
    Google Scholar
    48
    Viscosity of glass-forming liquids
    Mauro, John C.; Yue, Yuanzheng; Ellison, Adam J.; Gupta, Prabhat K.; Allan, Douglas C.
    Proceedings of the National Academy of Sciences of the United States of America (2009), 106 (47), 19780-19784CODEN: PNASA6; ISSN:0027-8424. (National Academy of Sciences)
    The low-temp. dynamics of ultraviscous liqs. hold the key to understanding the nature of glass transition and relaxation phenomena, including the potential existence of an ideal thermodn. glass transition. Unfortunately, existing viscosity models, such as the Vogel-Fulcher-Tammann (VFT) and Avramov-Milchev (AM) equations, exhibit systematic error when extrapolating to low temps. We present a model offering an improved description of the viscosity-temp. relationship for both inorg. and org. liqs. using the same no. of parameters as VFT and AM. The model has a clear phys. foundation based on the temp. dependence of configurational entropy, and it offers an accurate prediction of low-temp. isokoms without any singularity at finite temp. Our results cast doubt on the existence of a Kauzmann entropy catastrophe and assocd. ideal glass transition.
  49. 49
    Redlich, O.; Kister, A. T. Algebraic Representation of Thermodynamic Properties and the Classification of Solutions. Ind. Eng. Chem. 1948, 40, 345– 348,  DOI: 10.1021/ie50458a036
    Google Scholar
    There is no corresponding record for this reference.
  50. 50
    Tokuda, H.; Tsuzuki, S.; Susan, M. A. B. H.; Hayamizu, K.; Watanabe, M. How Ionic Are Room-Temperature Ionic Liquids? An Indicator of the Physicochemical Properties. J. Phys. Chem. B 2006, 110, 19593– 19600,  DOI: 10.1021/jp064159v
    Google Scholar
    50
    How Ionic Are Room-Temperature Ionic Liquids? An Indicator of the Physicochemical Properties
    Tokuda, Hiroyuki; Tsuzuki, Seiji; Susan, Md. Abu Bin Hasan; Hayamizu, Kikuko; Watanabe, Masayoshi
    Journal of Physical Chemistry B (2006), 110 (39), 19593-19600CODEN: JPCBFK; ISSN:1520-6106. (American Chemical Society)
    Room-temp. ionic liqs. (RTILs) are liqs. consisting entirely of ions, and their important properties, e.g., negligible vapor pressure, are considered to result from the ionic nature. However, we do not know how ionic the RTILs are. The ionic nature of the RTILs is defined in this study as the molar cond. ratio (Λimp/ΛNMR), calcd. from the molar cond. measured by the electrochem. impedance method (Λimp) and that estd. by use of pulse-field-gradient spin-echo NMR ionic self-diffusion coeffs. and the Nernst-Einstein relation (ΛNMR). This ratio is compared with solvatochromic polarity scales: anionic donor ability (Lewis basicity), ET(30), hydrogen bond donor acidity (α), and dipolarity/polarizability (π*), as well as NMR chem. shifts. The Λimp/ΛNMR well illustrates the degree of cation-anion aggregation in the RTILs at equil., which can be explained by the effects of anionic donor and cationic acceptor abilities for the RTILs having different anionic and cationic backbone structures with fixed counterparts, and by the inductive and dispersive forces for the various alkyl chain lengths in the cations. As a measure of the electrostatic interaction of the RTILs, the effective ionic concn. (Ceff), which is a dominant parameter for the electrostatic forces of the RTILs, was introduced as the product of Λimp/ΛNMR and the molar concn. and was compared with some phys. properties, such as reported normal b.ps. and distn. rates, glass transition temp., and viscosity. A decrease in Ceff of the RTILs is well correlated with the normal b.p. and distn. rate, whereas the liq.-state dynamics is controlled by a subtle balance between the electrostatic and other intermol. forces.
  51. 51
    Kapadi, U. R.; Hundiwale, D. G.; Patil, N. B.; Lande, M. K.; Patil, P. R. Studies of Viscosity and Excess Molar Volume of Binary Mixtures of Propane-1,2-diol with Water at Various Temperatures. Fluid Phase Equilib. 2001, 192, 63– 70,  DOI: 10.1016/S0378-3812(01)00621-5
    Google Scholar
    51
    Studies of viscosity and excess molar volume of binary mixtures of propane-1,2 diol with water at various temperatures
    Kapadi, U. R.; Hundiwale, D. G.; Patil, N. B.; Lande, M. K.; Patil, P. R.
    Fluid Phase Equilibria (2001), 192 (1-2), 63-70CODEN: FPEQDT; ISSN:0378-3812. (Elsevier Science B.V.)
    The excess molar volume VE, viscosity deviation Δη and excess Gibbs free energy of activation ΔG*E of viscous flow have been investigated from the d. and viscosity measurements of propane-1,2 diol (1) + water (2) over the entire range of mole fractions at 303.15, 308.15, 313.15 and 318.15 K. The results were fitted by Redlich-Kister equation. The system exhibited very large neg. values of VE due to increased interactions between unlike mols. or very large differences in the molar volumes of pure components at low temp.
  52. 52
    Anouti, M.; Vigeant, A.; Jacquemin, J.; Brigouleix, C.; Lemordant, D. Volumetric Properties, Viscosity and Refractive Index of the Protic Ionic Liquid, Pyrrolidinium Octanoate, in Molecular Solvents. J. Chem. Thermodyn. 2010, 42, 834– 845,  DOI: 10.1016/j.jct.2010.01.013
    Google Scholar
    52
    Volumetric properties, viscosity and refractive index of the protic ionic liquid, pyrrolidinium octanoate, in molecular solvents
    Anouti, Meriem; Vigeant, Annie; Jacquemin, Johan; Brigouleix, Catherine; Lemordant, Daniel
    Journal of Chemical Thermodynamics (2010), 42 (7), 834-845CODEN: JCTDAF; ISSN:0021-9614. (Elsevier Ltd.)
    Densities (ρ) and viscosities (η) of binary mixts. contg. the Protic Ionic Liq. (PIL), pyrrolidinium octanoate with 5 mol. solvents: water, methanol, ethanol, n-butanol, and acetonitrile are detd. at the atm. pressure as a function of the temp. and within the whole compn. range. The refractive index of all mixts. (nD) is measured at 298.15 K. The excess molar volumes VE and deviation from additivity rules of viscosities ηE and refractive index Δφn, of pyrrolidinium octanoate solns. were then deduced from the exptl. results as well as apparent molar volumes Vφi, partial molar volumes ‾Vm,i and thermal expansion coeffs. αp. The excess molar volumes VE are neg. over the entire mole fraction range for mixt. with water, acetonitrile, and methanol indicating strong hydrogen-bonding interaction for the entire mole fraction. In the case of longest carbon chain alcs. (such as ethanol and n-butanol) + pyrrolidinium octanoate solns., the VE variation as a function of the compn. describes an S shape. The deviation from additivity rules of viscosities is neg. over the entire compn. range for the acetonitrile, methanol, ethanol, and butanol, and becomes less neg. with increasing temp. Whereas, ηE of the {[Pyrr][C7CO2] + water} binary mixts. is pos. in the whole mole fraction range and decreases with increasing temp. the excess Gibbs free energies of activation of viscous flow (ΔG*E) for these systems were calcd. The deviation from additivity rules of refractive index Δφn are pos. over the whole compn. range and approach a max. of 0.25 in PIL mole fraction for all systems. The magnitude of deviation for Δφn describes the following order: Water > methanol > acetonitrile > ethanol. Results were discussed in terms of mol. interactions and mol. structures in these binary mixts.
  53. 53
    Workman, Jr., J.; Weyer, L. Practical Guide and Spectral Atlas for Interpretive Near-Infrared Spectroscopy; CRC Press, 2007.
    Google Scholar
    There is no corresponding record for this reference.
  54. 54
    Noda, I.; Ozaki, Y. Two-dimensional Correlation Spectroscopy – Applications in Vibrational and Optical Spectroscopy; John Wiley & Sons Ltd., 2004.
    Google Scholar
    There is no corresponding record for this reference.
  55. 55
    Haufa, K. Z.; Czarnecki, M. A. Effect of Temperature and Water Content on The Structure of 1,2-Propanediol and 1,3-Propanediol: Near-Infrared Spectroscopic Study. Vib. Spectrosc. 2009, 51, 80– 85,  DOI: 10.1016/j.vibspec.2008.10.013
    Google Scholar
    55
    Effect of temperature and water content on the structure of 1,2-propanediol and 1,3-propanediol: Near-infrared spectroscopic study
    Haufa, Krzysztof Zdzislaw; Czarnecki, Miroslaw Antoni
    Vibrational Spectroscopy (2009), 51 (1), 80-85CODEN: VISPEK; ISSN:0924-2031. (Elsevier B.V.)
    Effect of temp. and water content on the structure of 1,2-propanediol (12PD) and 1,3-propanediol (13PD) in the liq. phase has been studied by Fourier-transform near-IR (FT-NIR) spectroscopy. In addn., the spectra of both diols in CCl4 solns. at various concns. were measured. The exptl. spectra were analyzed by two-dimensional (2D) correlation approach and chemometric methods. The present results give no evidence that 12PD form the intramol. hydrogen bonding. In contrast, significant amts. of 13PD mols. in dild. CCl4 soln. is involved in the intramol. hydrogen bonding. At higher concns. the intramol. hydrogen bonds are broken and replaced by the intermol. ones. The structure of pure liq. propanediols is detd. by the intermol. hydrogen bonding. Unlike for monohydroxyl alcs., addn. of water to propanediols leads to faster temp.-induced breaking of the hydrogen-bonded assocs. However, variation of water content at const. temp. does not influence the structure of both diols. In this respect behavior of propanediols is similar to that of the monohydric alcs. The mols. of water in the mixts. are hydrogen bonded to the diols and act as a double proton donor. This bonding appears to be stronger than that in bulk water.

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  • Abstract

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    Figure 1

    Figure 1. Variation of density with (a) mole fraction of [C2mim]C2H5SO4 and (b) temperature and variation of viscosity with (c) mole fraction (lines are for visual aids only) and (d) temperature for binary mixtures of [C2mim]C2H5SO4 and propane-1,2-diol. (Lines are predicted from the VFT equation.)

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    Figure 2

    Figure 2. Variation of (a) excess molar volumes, (b) dynamic viscosity deviations, (c) excess molar Gibbs free energy of activation for viscous flow, (d) Gibbs free energy, (e) enthalpy, and (f) entropy of activation for the viscous flow of binary mixtures of [C2mim]C2H5SO4 and propane-1,2-diol as a function of mole fraction of [C2mim]C2H5SO4 at various temperatures.

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    Figure 3

    Figure 3. NIR spectra of (a) pure propane-1,2-diol and (b) [C2mim]C2H5SO4 at temperatures from 293.15 to 313.15 K at 5 K intervals.

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    Figure 4

    Figure 4. (a) Synchronous and (b) asynchronous 2D NIR correlation spectra and loadings and scores (c) PC1 and (d) PC2 calculated from the temperature-dependent spectral changes (293.15 to 313.15 K) of pure propane-1,2-diol.

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    Scheme 1

    Scheme 1. Schematic Diagram of Molecular-Level Interaction of (a) Pure Propane-1,2-diol, (b) Pure [C2mim]C2H5SO4, (c) Binary Mixture of [C2mim]C2H5SO4 and Propane-1,2-diol When Mole Fraction of Propane-1,2-diol is Greater, and (d) Binary Mixture of [C2mim]C2H5SO4 and Propane-1,2-diol When Mole Fraction of [C2mim]C2H5SO4 is Greater
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  • References

    This article references 55 other publications.

    1. 1
      Freemantle, M. An Introduction to Ionic Liquids; RSC Publishing: Cambridge, UK, 2009.
      There is no corresponding record for this reference.
    2. 2
      Angell, C. A.; Ansari, Y.; Zhao, Z. Ionic Liquids: Past, Present and Future. Faraday Discuss. 2012, 154, 9– 27,  DOI: 10.1039/C1FD00112D
      2
      Ionic liquids: past, present and future
      Angell C Austen; Ansari Younes; Zhao Zuofeng
      Faraday discussions (2012), 154 (), 9-27; discussion 81-96, 465-71 ISSN:1359-6640.
      An overview of the field of low-melting ionic liquids is given from its inception in 1886 through to the present time. The subject is divided into an introductory section that summarizes the early history of the field, and differentiates its subsections, before addressing matters judged of some interest in "pre-surge" and "post-surge" stages of its development, focusing on physicochemical as opposed to the prolific synthetic and industrial aspects in which the author has no competence. We give a final section specifically to protic ionic liquids, which we consider to have particular scientific potential.
    3. 3
      Stalpaert, M.; Peeters, N.; de Vos, D. Conversion of Lactide to Acrylic Acid by a Phosphonium Ionic Liquid and Acid Cocatalyst. Catal. Sci. Technol. 2018, 8, 1468– 1474,  DOI: 10.1039/C7CY02364B
      3
      Conversion of lactide to acrylic acid by a phosphonium ionic liquid and acid cocatalyst
      Stalpaert, M.; Peeters, N.; De Vos, D.
      Catalysis Science & Technology (2018), 8 (5), 1468-1474CODEN: CSTAGD; ISSN:2044-4753. (Royal Society of Chemistry)
      Acrylic acid, an important starting compd. for a wide variety of consumer products, is generally produced through selective oxidn. of propene. A more sustainable approach would be its synthesis from lactic acid, since this compd. is generally produced by fermn. of renewable sugar streams. Up to now, most research on this reaction has involved gas phase reactions, which require high temps., often above 300 °C. Building on our previous work, which demonstrated the ionic liq. tetrabutylphosphonium bromide, combined with an acid cocatalyst, as an interesting catalyst for dehydration and dehydrohalogenation reactions, we here report the use of this catalytic system in the conversion of lactide to acrylic acid. Initial expts. showed the formation of the volatile side products ethylene, bromoethane and acetaldehyde, which could explain mass loss that was not well understood heretofore. A combination of liq. phase GC anal. and gas phase FTIR spectroscopy allowed us to close the mass balance. As a result, a reaction network was proposed and supported by exptl. studies. Finally, the insights in the reaction network were applied to achieve a very good acrylic acid yield of 70%.
    4. 4
      Yan, D.; Wang, G.; Gao, K.; Lu, X.; Xin, J.; Zhang, S. One-pot Synthesis of 2, 5-Furandicarboxylic Acid from Fructose in Ionic Liquids. Ind. Eng. Chem. Res. 2018, 57, 1851– 1858,  DOI: 10.1021/acs.iecr.7b04947
      4
      One-Pot Synthesis of 2,5-Furandicarboxylic Acid from Fructose in Ionic Liquids
      Yan, Dongxia; Wang, Gongying; Gao, Kai; Lu, Xingmei; Xin, Jiayu; Zhang, Suojiang
      Industrial & Engineering Chemistry Research (2018), 57 (6), 1851-1858CODEN: IECRED; ISSN:0888-5885. (American Chemical Society)
      2,5-Furandicarboxylic acid (FDCA), which is usually produced from HMF catalyzed by noble metal catalysts, is an important bio-based monomer for the degradable polymer polyethylene furandicarboxylate (PEF). In order to reduce the high costs of starting material and catalysts, a novel approach for the direct conversion of fructose into FDCA was developed by employing [Bmim]Cl as a solvent with non-noble metal (Fe-Zr-O) as a catalyst. Relatively high FDCA yield was obtained at full fructose conversion under optimal conditions. The kinetic study revealed that the oxidn. of intermediate FFCA to FDCA possessed the highest activation energy, indicating this step is most affected by reaction temp. Addnl., in the IL-promoted reaction system, other biomass sources, such as glucose, galactose, mannose, starch and cellulose also can be directly converted, with lower FDCA yield compared with that of fructose due to the ineffective isomerization of aldohexoses into fructose.
    5. 5
      Wei; Wang, Y.; Chen, J.; Xu, P.; Zhou, Y. Preparation of Ionic Liquid Modified Magnetic Metal-Organic Frameworks Composites for The Solid-Phase Extraction of α–Chymotrypsin. Talanta 2018, 182, 484– 491,  DOI: 10.1016/j.talanta.2018.02.022
      5
      Preparation of ionic liquid modified magnetic metal-organic frameworks composites for the solid-phase extraction of α-chymotrypsin
      Wei, Xiaoxiao; Wang, Yuzhi; Chen, Jing; Xu, Panli; Zhou, Yigang
      Talanta (2018), 182 (), 484-491CODEN: TLNTA2; ISSN:0039-9140. (Elsevier B.V.)
      A novel magnetic solid-phase extn. (MSPE) method based on 1-hexyl-3-Me imidazolium chloride ionic liq. (IL) modified magnetic Fe3O4 nanoparticles, hydroxylated multiwall carbon nanotubes (MWCNTs-OH) and zeolitic imidazolate frameworks (ZIFs) nanocomposites (Fe3O4-MWCNTs-OH@ZIF-67@IL) were proposed and applied to ext. α-chymotrypsin. The magnetic materials were synthesized successfully and characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), thermal gravimetric anal. (TGA), fourier transform IR spectrometry (FT-IR), vibrating sample magnetometer (VSM) and zeta potentials. Subsequently, the UV-vis spectrophotometer at about 280nm was utilized to quant. analyze the α-chymotrypsin concn. in the supernatant. Furthermore, single factor expts. revealed that the extn. capacity was influenced by initial α-chymotrypsin concn., ionic strength, extn. time, extn. temp. and pH value. The extn. capacity could reach up to about 635mgg-1 under the optimized conditions, absolutely higher than that of extn. for Ovalbumin (OVA), Bovine serum albumin (BSA) and Bovine Hb (BHb). In addn., the regeneration studies showed Fe3O4-MWCNTs-OH@ZIF-67@IL particles could be reused several times and kept a high extn. capacity. Besides, the study of enzymic activity also indicated that the activity of the extd. α-chymotrypsin was well maintained 93% of initial activity. What's more, the proposed method was successfully applied to ext. α-chymotrypsin in porcine pancreas crude ext. with satisfactory results. All of above conclusions highlight the great potential of the proposed Fe3O4-MWCNTs-OH@ZIF-67@IL-MSPE method in the anal. of biomols.
    6. 6
      Bogdanov, M. G.; Svinyarov, I. Efficient Purification of Halide-Based Ionic Liquids using Improved Apparatus for Continuous Liquid-Liquid Extraction. Sep. Purif. Technol. 2018, 196, 57– 60,  DOI: 10.1016/j.seppur.2017.07.039
      6
      Efficient purification of halide-based ionic liquids by means of improved apparatus for continuous liquid-liquid extraction
      Bogdanov, Milen G.; Svinyarov, Ivan
      Separation and Purification Technology (2018), 196 (), 57-60CODEN: SPUTFP; ISSN:1383-5866. (Elsevier B.V.)
      The purity level of Ionic liqs. (ILs) is a question of immense importance both from fundamental and applied standpoint. In order to improve the purifn. process of halide-based ILs, the latter being starting materials for the synthesis of a vast no. of other ILs, an app. is constructed for continuous liq.-liq. extn. to be used as a tool for purifn. after the quaternization step. The app. employs the heat of the evapg. solvent to heat up the extn. chamber, thus allowing the liq.-liq. extn. to be conducted at elevated temp. The latter improves the process efficiency due to facilitated mass transfer. The purifn. carried out with this tool proved successful in the removal of impurities such as residual starting compds. (N-methylimidazole and haloalkanes) under mild conditions and was shown to give ILs of high purity for considerably reduced consumption of org. solvent and technol. time.
    7. 7
      Rdzanek, P.; Marszalek, J.; Kaminski, W. Biobutanol Concentration by Pervaporation Using Supported Ionic Liquid Membranes. Sep. Purif. Technol. 2018, 196, 124– 131,  DOI: 10.1016/j.seppur.2017.10.010
      7
      Biobutanol concentration by pervaporation using supported ionic liquid membranes
      Rdzanek, P.; Marszalek, J.; Kaminski, W.
      Separation and Purification Technology (2018), 196 (), 124-131CODEN: SPUTFP; ISSN:1383-5866. (Elsevier B.V.)
      ABE fermn. uses anaerobic bacteria to produce acetone, butanol and ethanol from carbohydrates. Nowadays, ethanol is used as a petrol additive but butanol, due to its unique properties, can become a future biofuel. To recover n-butanol from the fermn. broth, pervaporation can be used. However, sepn. performance of pervaporation is limited by the polymeric membrane. This problem can be overcome by using an ionic liq., immobilized in the active layer of the membrane. This paper investigates the performance of supported ionic liq. membranes (SILMs) employed for the pervaporative concn. of n-butanol. In the study, two ionic liqs. (ILs), i.e. trihexyl(tetradecyl)phosphoniumtetracyanoborate (P6,6,6,14tcb) and 1-hexyl-3-methylimidazolium hexafluorophosphate (Im6,1hfp), were used. The ILs were immobilized with the help of polyether block amide (PEBA). To prevent the ionic liqs. from leaching out, addnl. polymeric coating was necessary. For this purpose, an addnl. amt. of PEBA was applied directly on the IL-PEBA layer. The pervaporation process was carried out at 29, 37 and 50°. The aq. feed soln. contained three org. components, i.e. acetone, butanol and ethanol in a 3:6:1 mass ratio. The concn. of butanol in the feed was 1.5, 3 and 5%. It was found that the permeation fluxes as well as selectivity of the SILMs could be influenced by different ILs. The highest permeation flux, equal to 6,5 kg/(M2 h), was obsd. for the membrane without an ionic liq. due to a higher water flux. However, the highest concn. of butanol in the permeate was achieved with the P6,6,6,14tcb membrane and the enrichment factor was found to be 14.93 while the selectivity for butanol in relation to water was equal to 8.34.
    8. 8
      Zhang, L.; Shu, Z.; Yang, N.; Wang, B.; Dou, H.; Zhang, N. Improvement in Antifouling and Separation Performance of PVDF Hybrid Membrane by Incorporation of Room Temperature Ionic Liquids Grafted Halloysite Nanotubes for Oil–Water Separation. J. Appl. Polym. Sci. 2018, 135, 46278,  DOI: 10.1002/app.46278
      There is no corresponding record for this reference.
    9. 9
      Wilkes, J. S.; Levisky, J. A.; Wilson, R. A.; Hussey, C. L. Dialkylimidazolium Chloroaluminate Melts: A New Class of Room-Temperature Ionic Liquids for Electrochemistry, Spectroscopy and Synthesis. Inorg. Chem. 1982, 21, 1263– 1264,  DOI: 10.1021/ic00133a078
      9
      Dialkylimidazolium chloroaluminate melts: a new class of room-temperature ionic liquids for electrochemistry, spectroscopy and synthesis
      Wilkes, John S.; Levisky, Joseph A.; Wilson, Robert A.; Hussey, Charles L.
      Inorganic Chemistry (1982), 21 (3), 1263-4CODEN: INOCAJ; ISSN:0020-1669.
      I (R = Me, Et, Pr, Bu) were prepd. by reaction of the analogous chlorides with AlCl3. I (R = Et) was superior to previous melts in terms of liquidus temp., electrochem. window, and reactivity with Al. It was similar to alkylpyridinium chloroaluminates in its viscosity, cond., wide range of Lewis acidity, and ability to dissolve org. and inorg. compds.
    10. 10
      Zhao, M.; Zheng, L.; Bai, X.; Li, N.; Yu, L. Fabrication of Silica Nanoparticles and Hollow Spheres Using Ionic Liquid Microemulsion Droplets as Templates. Colloids Surf., A 2009, 346, 229– 236,  DOI: 10.1016/j.colsurfa.2009.06.021
      10
      Fabrication of silica nanoparticles and hollow spheres using ionic liquid microemulsion droplets as templates
      Zhao, Mingwei; Zheng, Liqiang; Bai, Xiangtao; Li, Na; Yu, Li
      Colloids and Surfaces, A: Physicochemical and Engineering Aspects (2009), 346 (1-3), 229-236CODEN: CPEAEH; ISSN:0927-7757. (Elsevier B.V.)
      Silica products with 2 different morphologies were prepd. using nonaq. ionic liq. microemulsion droplets as templates. The morphologies of the obtained products were characterized by both TEM and SEM. By adjusting the reaction conditions, ellipsoidal nanoparticles were formed under acidic conditions, while hollow silica spheres were obtained under alk. conditions. The size distribution of hollow silica spheres was narrower than that of the ellipsoidal nanoparticles. The various vibration modes of different functional groups in the silica materials were revealed by FTIR spectroscopy. The two samples were both shown to be amorphous, not cryst. by x-ray diffraction (XRD). A simple diagram of the formation process including the hydrolysis and condensation reactions is given. Furthermore, a probable mechanism for the formation of silica materials under acidic or alk. conditions is presented, which may be helpful for better understanding the different silica materials obtained under different conditions.
    11. 11
      Li, Z.; Zhang, J.; Du, J.; Han, B.; Wang, J. Preparation of Silica Microrods with Nano-Sized Pores in Ionic Liquid Microemulsions. Colloids Surf., A 2006, 286, 117– 120,  DOI: 10.1016/j.colsurfa.2006.03.011
      11
      Preparation of silica microrods with nano-sized pores in ionic liquid microemulsions
      Li, Zhonghao; Zhang, Jianling; Du, Jimin; Han, Buxing; Wang, Jiaqiu
      Colloids and Surfaces, A: Physicochemical and Engineering Aspects (2006), 286 (1-3), 117-120CODEN: CPEAEH; ISSN:0927-7757. (Elsevier B.V.)
      The microemulsions with ionic liq. (IL) as continuous phase were used to fabricate silica microrods. Porous silica microrods with nano-sized pores could be prepd. in this new type of microemulsions. The effects of water-to-surfactant molar ratio ( w ) and the adding amt. of tetraethylorthosilicate (TEOS) on the morphologies of the obtained silica were studied. SEM, TEM and electron diffraction (ED) were used to characterize the as-prepd. products.
    12. 12
      Moniruzzaman, M.; Kamiya, N.; Goto, M. Biocatalysis in Water-in-ionic Liquid Microemulsions: A Case Study with Horseradish Peroxidase. Langmuir 2009, 25, 977– 982,  DOI: 10.1021/la803118q
      12
      Biocatalysis in Water-in-Ionic Liquid Microemulsions: A Case Study with Horseradish Peroxidase
      Moniruzzaman, M.; Kamiya, N.; Goto, M.
      Langmuir (2009), 25 (2), 977-982CODEN: LANGD5; ISSN:0743-7463. (American Chemical Society)
      In this article we report the first results on the enzymic activity of horseradish peroxidase (HRP) microencapsulated in water-in-ionic liq. (w/IL) microemulsions using pyrogallol as the substrate. Toward this goal, the system used in this study was composed of anionic surfactant AOT (sodium bis(2-ethyl-1-hexyl)sulfosuccinate)/hydrophobic IL [C8mim][Tf2N] (1-octyl-3-Me imidazolium bis(trifluoromethylsulfonyl)amide)/water/1-hexanol. In this system, the catalytic activity of HRP was measured as a function of substrate concns., W (molar ratio of water to surfactant), pH, and 1-hexanol content. The curve of the activity-W profile was found to be hyperbolic for the new microemulsion. The apparent Michaelis-Menten kinetic parameters (kcat and Km) were estd. and compared to those obtained from a conventional microemulsion. Apparently, it was found that HRP-catalyzed oxidn. of pyrogallol by hydrogen peroxide in IL microemulsuions is much more effective than in a conventional AOT/water/isooctane microemulsion. The stability of HRP solubilized in the newly developed w/IL microemulsions was examd., and it was found that HRP retained almost 70% of its initial activity after incubation at 28° for 30 h.
    13. 13
      Pavlidis, I. V.; Gournis, D.; Papadopoulos, G. K.; Stamatis, H. Lipases in Water-in-Ionic Liquid Microemulsions: Structural and Activity Studies. J. Mol. Catal. B 2009, 60, 50– 56,  DOI: 10.1016/j.molcatb.2009.03.007
      13
      Lipases in water-in-ionic liquid microemulsions: Structural and activity studies
      Pavlidis, Ioannis V.; Gournis, Dimitrios; Papadopoulos, George K.; Stamatis, Haralambos
      Journal of Molecular Catalysis B: Enzymatic (2009), 60 (1-2), 50-56CODEN: JMCEF8; ISSN:1381-1177. (Elsevier B.V.)
      Water-in-ionic liq. (w/IL) microemulsions formulated with non-ionic surfactants, (Tween 20 or Triton X-100) in 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim]PF6), were used as media for lipase-catalyzed esterification reactions. The catalytic behavior and stability of lipases from Candida rugosa, Chromobacterium viscosum and Thermomyces lanuginosa in these novel microemulsions were investigated and compared to other microheterogeneous media used so far for enzyme-catalyzed reactions. The catalytic behavior of the enzymes depends strongly on the surfactant concn. and the water content. The dependence of the esterification activity of lipases on molar ratio of water to surfactant (wo) follows a bell-shaped profile, presenting a max. at wo ≈ 5. The operational stability of lipases in w/IL microemulsions, esp. at high incubation temp. (50°), was significantly increased compared to that obsd. in other microheterogeneous media. The highest half-life times (>100 h) were obtained in w/IL microemulsions with low water content. Conformational studies via Fourier transform-IR (FT-IR) and CD spectroscopy indicated that lipases entrapped in w/IL microemulsions in most cases retain their native structure or adapt a more rigid structure compared to other microheterogeneous media, which correlated well with the stability results. A simple procedure suitable for ester sepn. and enzyme reuse was developed. T. lanuginosa lipase retained 90% of activity after ten reaction cycles in w/IL microemulsions formulated with Tween 20.
    14. 14
      Zheng, W.; Huang, K.; Wu, Y.; Hu, X. Protic Ionic Liquid as Excellent Shuttle of MDEA for Fast Capture of CO2. AIChE J. 2018, 64, 209– 219,  DOI: 10.1002/aic.15921
      14
      Protic ionic liquid as excellent shuttle of MDEA for fast capture of CO2
      Zheng, Wen-Tao; Huang, Kuan; Wu, You-Ting; Hu, Xing-Bang
      AIChE Journal (2018), 64 (1), 209-219CODEN: AICEAC; ISSN:0001-1541. (John Wiley & Sons, Inc.)
      An inexpensive protic ionic liq. (PIL), 3-(dimethylamino)-1-propylamine acetate [DMAPAH][Ac], was examd. as an activator of N-methyldiethanolamine (MDEA) for fast flue gas CO2 absorption. PIL-activated MDEA solns. had excellent absorption rate and capacity (≥2.5 mol/kg) performance. A novel absorption mechanism is proposed to account for this phenomenon; the PIL shuttling role is described in detail. Also, enthalpy change ΔHSOL (-45 to -52 kJ/mol), PIL turnover no., and regeneration efficiency (>92%) were measured. These data showed PIL-mediated MDEA solns. may be used as promising absorbents for fast flue gas CO2 capture. © 2017 American Institute of Chem. Engineers AIChE J, 2017.
    15. 15
      Yang, X.; Song, H.; Wang, J.; Zou, W. Temperature and Composition Dependence of The Density, Viscosity and Refractive Index of Binary Mixtures of a Novel Gemini Ionic Liquid with Acetonitrile. RSC Adv. 2016, 6, 29172– 29181,  DOI: 10.1039/C5RA27934H
      15
      Temperature and composition dependence of the density, viscosity and refractive index of binary mixtures of a novel gemini ionic liquid with acetonitrile
      Yang, Xuzhao; Song, Hao; Wang, Jun; Zou, Wenyuan
      RSC Advances (2016), 6 (35), 29172-29181CODEN: RSCACL; ISSN:2046-2069. (Royal Society of Chemistry)
      A novel asym. gemini ionic liq., 1-(1-methypiperidinium-1-yl)hexane-(1-pyridinium)bi[bis(trifluoromethanesulfonyl)imide] ([MPiC6Py][NTf2]2) was synthesized and characterized by 1H NMR, 13C NMR and IR. Elemental anal. was performed on a Vario EL III instrument. Densities, viscosities and refractive indexes were measured for the binary mixt. of [MPiC6Py][NTf2]2 with acetonitrile over the entire range of mole fractions at temps. from T = (293.15 to 323.15) K under the atm. pressure of 0.1 MPa. Using the basic exptl. data, the excess molar volumes (VEm), the viscosity deviations (Δη) and the refractive index deviations (ΔnD) for the binary systems were calcd. and correlated to the Redlich-Kister polynomial to est. coeffs. and the std. deviation between the exptl. and calcd. values. The neg. values of VEm and Δη result from strong self-assocn. and weak hydrogen bonding interactions between the mols. of [MPiC6Py][NTf2]2 and acetonitrile. The values of ΔnD are all pos. for the binary mixts. and increase with increasing temp. The enthalpy, entropy and excess Gibbs energy of activation of the viscous flow of the binary mixts. also have been detd. The values of molar refraction and polarizability indicate that the dominant interactions between [MPiC6Py][NTf2]2 and acetonitrile are dipole-dipole mol. interactions. The obtained results are hoped to provide helpful information for the fundamental physicochem. properties of asym. gemini ionic liqs. and their further industrial applications.
    16. 16
      Tokuda, H.; Hayamizu, K.; Ishii, K.; Susan, M. A. B. H.; Watanabe, M. Physicochemical Properties and Structures of Room Temperature Ionic Liquids. 1. Variation of Anionic Species. J. Phys. Chem. B 2004, 108, 16593– 16600,  DOI: 10.1021/jp047480r
      16
      Physicochemical Properties and Structures of Room Temperature Ionic Liquids. 1. Variation of Anionic Species
      Tokuda, Hiroyuki; Hayamizu, Kikuko; Ishii, Kunikazu; Susan, Md. Abu Bin Hasan; Watanabe, Masayoshi
      Journal of Physical Chemistry B (2004), 108 (42), 16593-16600CODEN: JPCBFK; ISSN:1520-6106. (American Chemical Society)
      Room-temp. ionic liqs. (RTILs) based on 1-butyl-3-methylimidazolium ([bmim]) with a variety of fluorinated anions were prepd., and the thermal behavior, d., viscosity, self-diffusion coeffs. of the cations and anions, and ionic cond. were measured over a wide temp. range. The temp. dependencies of the self-diffusion coeff., viscosity, ionic cond., and molar cond. have been fitted to the Vogel-Fulcher-Tamman equation, and the best-fit parameters for the self-diffusion coeff., viscosity, ionic cond., and molar cond. have been estd., together with the linear fitting parameters for the d. The self-diffusion coeffs. detd. for the individual ions by pulsed-field-gradient spin-echo NMR method exhibit higher values for the cation compared with the anion over a wide temp. range, even if its radius is larger than that of the anionic radii. The summation of the cationic and anionic diffusion coeffs. for the RTILs follows the order [bmim][(CF3SO2)2N] > [bmim][CF3CO2] > [bmim][CF3SO3] > [bmim][BF4] > [bmim][(C2F5SO2)2N] > [bmim][PF6] at 30 °C, and the order of the diffusion coeffs. greatly contrasts to the viscosity data. The ionic assocn. is proposed from the results of the ratios of molar cond. obtained from impedance measurements to that calcd. by the ionic diffusivity using the Nernst-Einstein equation. The ratio for the ionic liqs. follows the order [bmim][PF6] > [bmim][BF4] > [bmim][(C2F5SO2)2N] > [bmim][(CF3SO2)2N] > [bmim][CF3SO3] > [bmim][CF3CO2] at 30 °C and provides quant. information on the active ions contributing to ionic conduction in the diffusion components.
    17. 17
      Tokuda, H.; Hayamizu, K.; Ishii, K.; Susan, M. A. B. H.; Watanabe, M. Physicochemical Properties and Structures of Room Temperature Ionic Liquids. 2. Variation of Alkyl Chain Length in Imidazolium Cation. J. Phys. Chem. B 2005, 109, 6103– 6110,  DOI: 10.1021/jp044626d
      17
      Physicochemical Properties and Structures of Room Temperature Ionic Liquids. 2. Variation of Alkyl Chain Length in Imidazolium Cation
      Tokuda, Hiroyuki; Hayamizu, Kikuko; Ishii, Kunikazu; Susan, Md. Abu Bin Hasan; Watanabe, Masayoshi
      Journal of Physical Chemistry B (2005), 109 (13), 6103-6110CODEN: JPCBFK; ISSN:1520-6106. (American Chemical Society)
      The alkyl chain length of 1-alkyl-3-methylimidazolium bis(trifluoromethane sulfonyl)imide ([Rmim][(CF3SO2)2N], R = Me (m), Et (e), Bu (b), hexyl (C6), and octyl (C8)) was varied to prep. a series of room-temp. ionic liqs. (RTILs), and the thermal behavior, d., viscosity, self-diffusion coeffs. of the cation and anion, and ionic cond. were measured over a wide temp. range. The self-diffusion coeff., viscosity, ionic cond., and molar cond. change with temp. following the Vogel-Fulcher-Tamman equation, and the d. shows a linear decrease. The pulsed-field-gradient spin-echo NMR method reveals a higher self-diffusion coeff. for the cation compared to that for the anion over a wide temp. range, even if the cationic radius is larger than that of the anion. The summation of the cationic and anionic diffusion coeffs. for the RTILs follows the order [emim][(CF3SO2)2N] > [mmim][(CF3SO2)2N] > [bmim][(CF3SO2)2N] > [C6mim][(CF3SO2)2N] > [C8mim][(CF3SO2)2N], which greatly contrasts to the viscosity data. The ratio of molar cond. obtained from impedance measurements to that calcd. by the ionic diffusivity using the Nernst-Einstein equation quantifies the active ions contributing to ionic conduction in the diffusion components, in other words, ionicity of the ionic liqs. The ratio decreases with increasing no. of carbon atoms in the alkyl chain. Finally, a balance between the electrostatic and induction forces has been discussed in terms of the main contribution factor in detg. the physicochem. properties.
    18. 18
      Tokuda, H.; Ishii, K.; Susan, M. A. B. H.; Tsuzuki, S.; Hayamizu, K.; Watanabe, M. Physicochemical Properties and Structures of Room Temperature Ionic Liquids. 3. Variation of Cationic Structures. J. Phys. Chem. B 2006, 110, 2833– 2839,  DOI: 10.1021/jp053396f
      18
      Physicochemical Properties and Structures of Room-Temperature Ionic Liquids. 3. Variation of Cationic Structures
      Tokuda, Hiroyuki; Ishii, Kunikazu; Susan, Md. Abu Bin Hasan; Tsuzuki, Seiji; Hayamizu, Kikuko; Watanabe, Masayoshi
      Journal of Physical Chemistry B (2006), 110 (6), 2833-2839CODEN: JPCBFK; ISSN:1520-6106. (American Chemical Society)
      A series of room-temp. ionic liqs. (RTILs) were prepd. with different cationic structures, 1-butyl-3-methylimidazolium ([bmim]), 1-butylpyridinium ([bpy]), N-butyl-N-methylpyrrolidinium, ([bmpro]), and N-butyl-N,N,N-trimethylammonium ([(n-C4H9)(CH3)3N]) combined with an anion, bis(trifluoromethane sulfonyl)imide ([(CF3SO2)2N]), and the thermal property, d., self-diffusion coeffs. of the cation and anion, viscosity, and ionic cond. were measured over a wide temp. range. The self-diffusion coeff., viscosity, ionic cond., and molar cond. follow the Vogel-Fulcher-Tamman equation for temp. dependencies, and the best-fit parameters have been estd., together with the linear fitting parameters for the d. The relative cationic and anionic self-diffusion coeffs. for the RTILs, independently detd. by the pulsed-field-gradient spin-echo NMR method, appear to be influenced by the shape of the cationic structure. A definite order of the summation of the cationic and anionic diffusion coeffs. for the RTILs: [bmim][(CF3SO2)2N] > [bpy][(CF3SO2)2N] > [bmpro][(CF3SO2)2N] > [(n-C4H9)(CH3)3N][(CF3SO2)2N], has been obsd., which coincides with the reverse order to the viscosity data. The ratio of molar cond. obtained from the impedance measurements to that calcd. by the ionic diffusivity using the Nernst-Einstein equation quantifies the active ions contributing to ionic conduction in the diffusion components and follows the order: [bmpro][(CF3SO2)2N] > [(n-C4H9)(CH3)3N][(CF3SO2)2N] > [bpy][(CF3SO2)2N] > [bmim][(CF3SO2)2N] at 30 °C.
    19. 19
      Pereiro, B. A.; Rodriguez, A. P. Thermodynamic Properties of Ionic Liquids in Organic Solvents from (293.15 to 303.15) K. J. Chem. Eng. Data 2007, 52, 600– 608,  DOI: 10.1021/je060497d
      19
      Thermodynamic Properties of Ionic Liquids in Organic Solvents from (293.15 to 303.15) K
      Pereiro, Ana B.; Rodriguez, Ana
      Journal of Chemical & Engineering Data (2007), 52 (2), 600-608CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
      Densities, speeds of sound, and refractive indexes of the binary mixts. of BMIM PF6 (1-butyl-3-Me imidazolium hexafluorophosphate), HMIM PF6 (1-hexyl-3-methylimidazolium hexafluorophosphate), OMIM PF6 (1-methyl-3-octylimidazolium hexafluorophosphate), and MMIM CH3SO4 (1,3-dimethylimidazolium Me sulfate) with 2-butanone, ethylacetate, and 2-propanol were detd. from (293.15 to 303.15) K. Excess molar volumes, changes of refractive index on mixing, and deviations in isentropic compressibility were calcd. for the above systems. The liq.-liq. equil. data of the binary mixts. ionic liq. + 2-propanol were carried out, and they were compared with the correlated values obtained by means of the NRTL and UNIQUAC equations.
    20. 20
      AlTwaim, M. S.; Al-Jimaz, A. S.; Alkhaldi, K. H. A. E. Liquid Extraction of Toluene from Heptane, Octane or Nonane Using Mixed Ionic Solvents of 1-Ethyl-3- methylimidazolium Methylsulfate and 1-Hexyl-3-methylimidazolium Hexafluorophosphate. J. Chem. Eng. Data 2019, 64, 169– 175,  DOI: 10.1021/acs.jced.8b00669
      There is no corresponding record for this reference.
    21. 21
      Garcıa-Miaja, G.; Troncoso, J.; Romanı, L. Excess Enthalpy, Density, And Heat Capacity for Binary Systems of Alkylimidazolium-based Ionic Liquids and Water. J. Chem. Thermodyn. 2009, 41, 161– 166,  DOI: 10.1016/j.jct.2008.10.002
      21
      Excess enthalpy, density, and heat capacity for binary systems of alkylimidazolium-based ionic liquids+water
      Garcia-Miaja, Gonzalo; Troncoso, Jacobo; Romani, Luis
      Journal of Chemical Thermodynamics (2009), 41 (2), 161-166CODEN: JCTDAF; ISSN:0021-9614. (Elsevier Ltd.)
      Exptl. measurements of excess molar enthalpy, d., and isobaric molar heat capacity are presented for a set of binary systems ionic liq. + water as a function of temp. at atm. pressure. The studied ionic liqs. are 1-butyl-3-methylpyridinium tetrafluoroborate, 1-ethyl-3-methylimidazolium ethylsulfate, 1-butyl-3-methylimidazolium methylsulfate, 1-butyl-3-methylimidazolium trifluoromethanesulfonate, and 1-ethyl-3-methylimidazolium trifluoromethanesulfonate. Excess molar enthalpy was measured at 303.15 K whereas d. and heat capacity were detd. within the temp. range 293.15 to 318.15 K. From exptl. data, excess molar volume and excess molar isobaric heat capacity were calcd. The anal. of the excess properties reveals important differences between the studied ionic liqs. which can be ascribed to their capability to form hydrogen bonds with water mols.
    22. 22
      Gonzalez, E. J.; Gonzalez, B.; Calvar, N.; Domınguez, A. Physical Properties of Binary Mixtures of the Ionic Liquid 1-Ethyl-3-Methylimidazolium Ethyl Sulfate with Several Alcohols at T = (298.15, 313.15, and 328.15) K and Atmospheric Pressure. J. Chem. Eng. Data 2007, 52, 1641– 1648,  DOI: 10.1021/je700029q
      22
      Physical properties of binary mixtures of the ionic liquid 1-ethyl-3-methylimidazolium ethyl sulfate with several alcohols at T = (298.15, 313.15, and 328.15) K and atmospheric pressure
      Gonzalez, Emilio J.; Gonzalez, Begona; Calvar, Noelia; Dominguez, Angeles
      Journal of Chemical & Engineering Data (2007), 52 (5), 1641-1648CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
      In this contribution, dynamic viscosities, densities, and speeds of sound of 1-ethyl-3-methylimidazolium Et sulfate (EMISE) with methanol, 1-propanol, and 2-propanol at T = (298.15, 313.15, and 328.15) K and refractive indexes at T = 298.15 K and at atm. pressure have been measured over the whole compn. range. Excess molar volumes, excess molar isentropic compressibilities, and viscosity deviations for the binary systems from T = 298.15 K to T = 328.15 K and refractive deviations at 298.15 K have been calcd. and were satisfactorily fitted to a Redlich-Kister equation to give the fitting parameters and the root-mean-square deviations.
    23. 23
      Lehmann, J.; Rausch, M. H.; Leipertz, A.; Fröba, A. P. Densities and Excess Molar Volumes for Binary Mixtures of Ionic Liquid 1-Ethyl-3-Methylimidazolium Ethylsulfate with Solvents. J. Chem. Eng. Data 2010, 55, 4068– 4074,  DOI: 10.1021/je1002237
      23
      Densities and Excess Molar Volumes for Binary Mixtures of Ionic Liquid 1-Ethyl-3-methylimidazolium Ethylsulfate with Solvents
      Lehmann, Julia; Rausch, Michael H.; Leipertz, Alfred; Froeba, Andreas P.
      Journal of Chemical & Engineering Data (2010), 55 (9), 4068-4074CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
      In this work d. data for binary mixts. of the ionic liq. 1-ethyl-3-methylimidazolium ethylsulfate ([EMIM][EtSO4]) with acetone, acetonitrile, propylene carbonate, dichloromethane, methanol, ethanol, and water are presented. Measurements were performed in dependence on compn. for temps. from (278.15 to 308.15) K using the vibrating-tube method with an expanded relative uncertainty (k = 2) of less than ± 0.02 %. All calcd. excess molar volumes are neg., indicating denser mol. packing than in the pure liqs. The size and the structure of the solvent mols. as well as the nature of interaction between all mixt. components seem to affect the extent of the obsd. compression effect.
    24. 24
      Kiefer, J.; Molina, M. M.; Noack, K. The Peculiar Nature of Molecular Interactions between an Imidazolium Ionic Liquid and Acetone. ChemPhysChem 2012, 13, 1213– 1220,  DOI: 10.1002/cphc.201100845
      24
      The Peculiar Nature of Molecular Interactions between an Imidazolium Ionic Liquid and Acetone
      Kiefer, Johannes; Molina, Marta Martinez; Noack, Kristina
      ChemPhysChem (2012), 13 (5), 1213-1220CODEN: CPCHFT; ISSN:1439-4235. (Wiley-VCH Verlag GmbH & Co. KGaA)
      We present novel insights into the mol. interactions between polar solvents and imidazolium ionic liqs. using the example of 1-ethyl-3-methylimidazolium Et sulfate and acetone. Recently published volumetric property data of this particular system have revealed peculiarities which could not be fully explained by steric effects. In order to shed light on the behavior at a mol. level, we apply IR spectroscopy and analyze solvent-induced line shifts as well as the excess IR spectra. From the spectroscopic results a conclusive picture of the site-specific mol. interactions is developed and our explanation is in concert with the volumetric effects. The data suggest the initial formation of trimers in which acetone interacts with existing ion pairs through interactions of the acetone oxygen atom with the imidazolium ring rather than forming directed hydrogen bonds at the CH moieties. With further addn. of acetone, tetramers are formed which significantly weaken the interionic interactions and eventually initiate ion pair dissocn. Once the ions are released, the anion is rapidly satd. with acetone while the cation solvation proceeds more slowly with acetone addn.
    25. 25
      Reddy, M. S.; Thomas, K.; Raju, S. S.; Nayeem, S. M.; Khan, I.; Krishana, K. B. M.; Babu, B. H. Excess Thermodynamic Properties for Binary Mixtures of Ionic Liquid 1-Ethyl-3-methylimidazolium EthylSulfate and 2-Methoxyethanol from T (298.15 to 328.15) K at Atmospheric Pressure. J. Solution Chem. 2016, 45, 675– 701,  DOI: 10.1007/s10953-016-0465-y
      25
      Excess Thermodynamic Properties for Binary Mixtures of Ionic Liquid 1-Ethyl-3-methylimidazolium Ethyl Sulfate and 2-Methoxyethanol from T = (298.15 to 328.15) K at Atmospheric Pressure
      Reddy, M. Srinivasa; Raju, K. Thomas S. S.; Nayeem, Sk. Md.; Khan, Imran; Krishana, K. B. M.; Babu, B. Hari
      Journal of Solution Chemistry (2016), 45 (5), 675-701CODEN: JSLCAG; ISSN:0095-9782. (Springer)
      The d. (ρ), speed of sound (u) and refractive index (nD) for pure [Emim][EtSO4], 2-methoxyethanol and their binary mixts. were measured using an Anton Paar vibrating tube d. and sound velocity meter (DSA 5000 M) and automatic refractometer over the whole compn. range as a function of temp. between 298.15 and 328.15 K in steps of 10 K at atm. pressure. Exptl. values were used to calc. the excess values of molar volumes (VEm), partial molar volumes (‾VEm), partial molar volumes at infinite diln. (‾VE,∞m), isentropic compressibility (κES), acoustic impedance (ZE), free length (LEf), speeds of sound (uE), internal pressure (πEi), free vol. (VEf) and deviations in refractive index (Δ.vphi.nD) for the binary mixts. These properties were fitted to a Redlich-Kister type equation to obtain the binary coeffs. and the std. deviations. The neg. values of VEm, κES, LEf,αEp, and VEf and pos. values for ZE, uE,πEi, and Δ.vphi.nD indicate the existence of strong interactions between the components. This was further supported by IR spectroscopy anal.
    26. 26
      Liu, Q.; Ma, L.; Wang, S.; Ni, Z.; Fu, X.; Wang, J.; Zheng, Q. Study on the properties of density, viscosity, excess molar volume, and viscosity deviation of [C2mim][NTf2],[C2mmim][NTf2],[C4mim][NTf2], and [C4mmim][NTf2] with PC binary mixtures. J. Mol. Liq. 2021, 325, 114573  DOI: 10.1016/j.molliq.2020.114573
      26
      Study on the properties of density,viscosity ,excess molar volume,and viscosity deviation of [C2mim][NTf2], [C2mmim][NTf2], [C4mim][NTf2],and [C4mmim][NTf2] with PC binary mixtures
      Liu, Qingshan; Ma, Liansheng; Wang, Shuyi; Ni, Zhiying; Fu, Xiaoyi; Wang, Jian; Zheng, Qige
      Journal of Molecular Liquids (2021), 325 (), 114573CODEN: JMLIDT; ISSN:0167-7322. (Elsevier B.V.)
      The imidazolium type ionic liqs. (ILs) 1-alkyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl] imide ([C2 mim][NTf2] and [C4 mim][NTf2]) were synthesized. For comparing, the ILs with introduction of Me group 1-alkyl-2,3-dimethylimidazolium bis[(trifluoromethyl)sulfonyl]imide ([C2 mmim][NTf2] and [C4 mmim][NTf2]) were also prepd. The d. and viscosity of the systems composed of above ILs and propylene carbonate (PC) were detd. The detd. uncertainties are u(ρ) = 0.00010 g ·cm-3 for d. and ur(η) = 0.02 for viscosity, resp. The excess molar volumes, thermal expansion coeffs., viscosity deviations, and a-const. were calcd. According to Redlich-Kister equation, the relationship between excess molar volume, viscosity deviation and mole fraction was fitted. By comparing with the systems of the same ILs in other org. solvents, the above-mentioned properties were discussed and the influence of introduced methylene group and Me group on the above properties was analyzed.
    27. 27
      Fu, X.; Wang, S.; Huang, Y.; Yang, X.; Liu, Q.; Zheng, Q. Densities and apparent molar volumes of diluent solutions of [EmimNTf2],[BmimNTf2], and [BmmimNTf2] in DEGDME and TEGDME. J. Mol. Liq. 2021, 341, 117328  DOI: 10.1016/j.molliq.2021.117328
      27
      Densities and apparent molar volumes of diluent solutions of [EmimNTf2], [BmimNTf2], and [BmmimNTf2] in DEGDME and TEGDME
      Fu, Xiaoyi; Wang, Shuyi; Huang, Yulu; Yang, Xiaoxi; Liu, Qingshan; Zheng, Qige
      Journal of Molecular Liquids (2021), 341 (), 117328CODEN: JMLIDT; ISSN:0167-7322. (Elsevier B.V.)
      The densities of six diluents with molality of 0.0199 to 0.5070 mol·kg-1 were measured at atm. pressure from 293.15 to 328.15 K. The studied ionic liqs. (ILs) include 1-ethyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide ([Emim][NTf2]), 1-butyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide ([Bmim][NTf2]), and 1-butyl-2,3-dimethylimidazolium bis[(trifluoromethyl)sulfonyl]imide ([Bmmim][NTf2]). The solvents include diethylene glycol di-Me ether (DEGDME) and tetraethylene glycol di-Me ether (TEGDME). The measured densities were applied for calcn. of Vφ/m3A·mol-1 (apparent molar volume) from 293.15 K to 328.15 K. The influence of the introduction of methylene (-CH2-), Me (-CH3) groups, and the structure of solvents on the d., apparent molar volume were discussed in depth. Redlich-Rosenfeld-Meyer (RRM) equation was used to fit Vφ/m3A·mol-1 dependence on the molality of the six studied diluent solns. Two parameter of Vφ0/m3A·mol-1 (infinite diln. apparent molar volume) and Eφ0/m3A·mol-1A·K-1 (limiting apparent molar expansibility) were also been fitted and discussed based on the RRM equation and polynomial equation, resp. Besides, the interactions of ion-ion and ion-solvent were discussed according to the fitted parameters. The structure making or breaking were also discussed for IL in solvent.
    28. 28
      Liu, Q.; Dai, H.; Chi, H.; Shi, K.; Zheng, Q.; Qi, Y. The density and dynamic viscosity for dilute solutions of [Emim][NTf2][Bmim][NTf2], and [Bmmim][NTf2] in ethylene glycol. J. Mol. Liq. 2023, 371, 121080  DOI: 10.1016/j.molliq.2022.121080
      28
      The density and dynamic viscosity for dilute solutions of [Emim][NTf2] [Bmim][NTf2], and [Bmmim][NTf2] in ethylene glycol
      Liu, Qingshan; Dai, Haoqi; Chi, Hongyun; Shi, Ketian; Zheng, Qige; Qi, Yanxia
      Journal of Molecular Liquids (2023), 371 (), 121080CODEN: JMLIDT; ISSN:0167-7322. (Elsevier B.V.)
      In this paper, three dil. solns. were prepd. and studied for d. and dynamic viscosity measurement at different temp. ranges and molality ranges. The three dil. solns. are imidazolium cation ionic liqs. (ILs) and ethylene glycol (EG). The measured temp. ranges are (293.15-328.15) K for d. and (298.15-328.15) K for dynamic viscosity, resp. The molality ranges of IL in EG are (0.0100-0.5001) mol•kg-1. The ILs cations are 1-ethyl-3-methylimidazolium, 1-buty-3-methylimidazolium, and 1-butyl-2,3-dimethylimidazolium and anion is bis[(trifluoromethyl)sulfonyl]imide. The molality concn. dependence on apparent molar volume was fitted according to the Redlich-Rosenfeld-Meyer (RRM) equation. The obtained fitted values of apparent molar volumes of infinite diln. (V0Φ/m3•mol-1), Sv/m3•mol-3/2•kg1/2, and Bv/m3•mol-2•kg were used for anal. of ion-solvent interaction and ion-ion interaction in soln. The relative viscosities have also been calcd. from the dynamic viscosities at different temps. and substance concns. The relationship between the relative viscosity and substance concn. of dild. soln. has been characterized by the Jones-Dole equation. The fitted parameters of D and F from the Jones-Dole equation were used for the anal. of interaction changing of solute-solute and solute-solvent. The group introduction of -CH2- (methylene) on position 1 and -CH3 (methyl) on position 2 of imidazolium cation have also been discussed for interaction changing in IL and EG solvent soln. Through the anal. of IL microstructure change, the interaction forces were also described and discussed for the studied solns.
    29. 29
      Fernandes, R. L.; Hoga, H. E.; Torres, R. B. Molecular interactions of ionic liquid {n-butylammonium methanoate (N4Met)+ alcohols} at several temperatures: Thermodynamic and spectroscopic properties. J. Chem. Thermodyn. 2020, 148, 106140  DOI: 10.1016/j.jct.2020.106140
      29
      Molecular interactions of ionic liquid {n-butylammonium methanoate (N4Met) + alcohols} at several temperatures: Thermodynamic and spectroscopic properties
      Fernandes, Robert Lunkez; Hoga, Heloisa Emi; Torres, Ricardo Belchior
      Journal of Chemical Thermodynamics (2020), 148 (), 106140CODEN: JCTDAF; ISSN:0021-9614. (Elsevier Ltd.)
      New exptl. data for d., speed of sound and viscosity for binary mixts. of protic ionic liq. {n-butylammonium methanoate (N4Met) + ethanol, or +1-propanol, or +1-butanol, or +1-pentanol} were measured in the whole concn. range at different temps. T = (293.15-313.15) K and p = 92.3 kPa. These results were used to obtain derived mixts. and excess properties. Correlation for viscosity proposed by Grunberg-Nissan, Heric-Brewer, Van der Wyk and Katti-Chaudhri have been used to correlate the viscosity values for the binary mixts. To complement the thermodn. results, spectroscopic studies (1H NMR, 13C NMR, FTIR) have been performed.
    30. 30
      Hoga, H. E.; Fernandes, R. L.; Olivieri, G. V.; Torres, R. B. Molecular interactions of (ionic liquid butylammonium methanoate+ alcohols) at several temperatures. Part II: sec-Butylammonium methanoate (S4Met). J. Chem. Thermodyn. 2023, 178, 106970  DOI: 10.1016/j.jct.2022.106970
      There is no corresponding record for this reference.
    31. 31
      Masilo, K.; Bahadur, I. Intermolecular Interactions between 1-Ethyl-3-methylimidazolium-Based Ionic Liquids with Carboxylic Acid at Different Temperatures via Thermodynamic and Spectroscopic Studies. J. Chem. Eng. Data 2021, 66, 1211– 1230,  DOI: 10.1021/acs.jced.0c00728
      31
      Intermolecular Interactions between 1-Ethyl-3-methylimidazolium-Based Ionic Liquids with Carboxylic Acid at Different Temperatures via Thermodynamic and Spectroscopic Studies
      Masilo, Kgomotso; Bahadur, Indra
      Journal of Chemical & Engineering Data (2021), 66 (3), 1211-1230CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
      We studied the intermol. interactions of binary mixts. of 1-ethyl-3-methylimidazolium-based ionic liqs. (ILs) with acetic or propionic acid. The physicochem. behavior of the binary mixts. was investigated by measuring the thermophys. properties, including the d. (ρ), sound velocity (u), and refractive index (nD), over the complete range of the IL mole fraction at T = 293.15-333.15 K and p = 0.1 MPa. The surface tension (γ) of the binary mixts. was also measured at T = 298.15 K but not detd. under other studied temps. due to the lack of a temp. controller. The excess molar volumes (VmE), excess isentropic compressibilities (ksE), excess sound velocity (uE), intermol. free length (Lf), deviation in the refractive index (ΔnD), and deviation in the surface tension (Δγ) were detd. from exptl. results. These parameters were further fitted to the Redlich-Kister polynomial equation. FTIR studies of pure components and binary systems at an equimolar compn. were conducted to clarify results from thermodn. properties and also analyze the intermol. interactions occurring in the mixt. A survey on available literature data was carried out to compare with our exptl. data. The selected ILs allowed us to compare the influence of the anion on the thermophys. and thermodn. properties the mixts.
    32. 32
      Ali, M. A.; Susan, M. A. B. H. Volumetric and Spectroscopic Studies of 1-ethyl-3-methylimidazolium Ethylsulfate/Propane-1-ol Binary Mixtures at Different Temperatures. Spectr. Emerg. Sci. 2022, 2, 17– 28,  DOI: 10.55878/SES2022-2-2-5
      There is no corresponding record for this reference.
    33. 33
      Hofman, T.; Gołdon, A.; Nevines, A.; Letcher, T. M. Densities, excess volumes, isobaric expansivity, and isothermal compressibility of the (1-ethyl-3-methylimidazolium ethylsulfate+ methanol) system at temperatures (283.15 to 333.15) K and pressures from (0.1 to 35) MPa. J. Chem. Thermodyn. 2008, 40, 580– 591,  DOI: 10.1016/j.jct.2007.11.011
      33
      Densities, excess volumes, isobaric expansivity, and isothermal compressibility of the (1-ethyl-3-methylimidazolium ethylsulfate + methanol) system at temperatures (283.15 to 333.15)K and pressures from (0.1 to 35)MPa
      Hofman, Tadeusz; Goldon, Andrzej; Nevines, Ashley; Letcher, Trevor M.
      Journal of Chemical Thermodynamics (2008), 40 (4), 580-591CODEN: JCTDAF; ISSN:0021-9614. (Elsevier Ltd.)
      Densities of pure 1-ethyl-3-methylimidazolium ethylsulfate ionic liq. - [C2mim][EtSO4] and its mixts. with methanol were measured with an accuracy of ±0.2 kg m-3, over the temp. range 283.15-333.15 K and pressure range 0.1-35 MPa, using a vibrating tube densimeter. Excess vols. were calcd. directly from the exptl. densities. The latter data were correlated by the Tait equation with the temp. dependent parameters for the pure ionic liq. and by a van Laar-type equation, involving parameters dependent on temp. and pressure for the mixts. The isobaric expansivity, isothermal compressibility, and related excess properties were calcd. The exceptionally strong influence of pressure and temp. on these properties was obsd.
    34. 34
      Gómez, E.; González, B.; Calvar, N.; Tojo, E.; Domínguez, Á. Physical properties of pure 1-ethyl-3-methylimidazolium ethylsulfate and its binary mixtures with ethanol and water at several temperatures. J. Chem. Eng. Data 2006, 51, 2096– 2102,  DOI: 10.1021/je060228n
      34
      Physical properties of pure 1-ethyl-3-methylimidazolium ethylsulfate and Its binary mixtures with ethanol and water at several temperatures
      Gomez, Elena; Gonzalez, Begona; Calvar, Noelia; Tojo, Emilia; Dominguez, Angeles
      Journal of Chemical & Engineering Data (2006), 51 (6), 2096-2102CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
      This paper reports on the synthesis and the phys. properties of the ionic liq. 1-ethyl-3-methylimidazolium ethylsulfate (EMISE). Exptl. densities, speeds of sound and refractive indexes were detd. from (288.15 to 343.15) K. Dynamic viscosities were measured from (298.15 to 343.15) K and surface tension were measured from (288.15 to 313.15) K for pure ionic liq. Densities, dynamic viscosities, speeds of sound, and isentropic compressibilities have been detd. over the whole compn. range for ethanol (1) + EMISE (2) and water (1) + EMISE (2) binary systems at T = (298.15, 313.15, and 328.15) K and atm. pressure. Excess molar volumes, viscosity deviations, and deviations in isentropic compressibility for the binary systems were fitted to a Redlich-Kister equation to det. the fitting parameters and the root mean square deviations. Refractive indexes were measured at 298.15 K over the whole compn. range for the ethanol (1) + EMISE (2) and water (1) + EMISE (2) binary systems. The results were used to calc. deviations in the refractive index.
    35. 35
      Fröba, A. P.; Kremer, H.; Leipertz, A. Density, refractive index, interfacial tension, and viscosity of ionic liquids [EMIM][EtSO4],[EMIM][NTf2],[EMIM][N(CN)2], and [OMA][NTf2] in dependence on temperature at atmospheric pressure. J. Phys. Chem. B 2008, 112, 12420– 12430,  DOI: 10.1021/jp804319a
      35
      Density, refractive index, interfacial tension, and viscosity of ionic liquids [EMIM][EtSO4], [EMIM][NTf2], [EMIM][N(CN)2], and [OMA][NTf2] in dependence on temperature at atmospheric pressure
      Froba Andreas P; Kremer Heiko; Leipertz Alfred
      The journal of physical chemistry. B (2008), 112 (39), 12420-30 ISSN:1520-6106.
      The density, refractive index, interfacial tension, and viscosity of ionic liquids (ILs) [EMIM][EtSO 4] (1-ethyl-3-methylimidazolium ethylsulfate), [EMIM][NTf 2] (1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide), [EMIM][N(CN) 2] (1-ethyl-3-methylimidazolium dicyanimide), and [OMA][NTf 2] (trioctylmethylammonium bis(trifluoromethylsulfonyl)imide) were studied in dependence on temperature at atmospheric pressure both by conventional techniques and by surface light scattering (SLS). A vibrating tube densimeter was used for the measurement of density at temperatures from (273.15 to 363.15) K and the results have an expanded uncertainty ( k = 2) of +/-0.02%. Using an Abbe refractometer, the refractive index was measured for temperatures between (283.15 and 313.15) K with an expanded uncertainty ( k = 2) of about +/-0.0005. The interfacial tension was obtained from the pendant drop technique at a temperature of 293.15 K with an expanded uncertainty ( k = 2) of +/-1%. For higher and lower temperatures, the interfacial tension was estimated by an adequate prediction scheme based on the datum at 293.15 K and the temperature dependence of density. For the ILs studied within this work, at a first order approximation, the quantity directly accessible by the SLS technique was the ratio of surface tension to dynamic viscosity. By combining the experimental results of the SLS technique with density and interfacial tension from conventional techniques, the dynamic viscosity could be obtained for temperatures between (273.15 and 333.15) K with an estimated expanded uncertainty ( k = 2) of less than +/-3%. The measured density, refractive index, and viscosity are represented by interpolating expressions with differences between the experimental and calculated values that are comparable with but always smaller than the expanded uncertainties ( k = 2). Besides a comparison with the literature, the influence of structural variations on the thermophysical properties of the ILs is discussed in detail. The viscosities mostly agree with values reported in the literature within the combined estimated expanded uncertainties ( k = 2) of the measurements while our density and interfacial tension data differ by more than +/-1% and +/-5%.
    36. 36
      Zarei, H.; Golroudbari, S. A.; Behroozi, M. Experimental studies on volumetric and viscometric properties of binary and ternary mixtures of N, N-dimethylacetamide, N-methylformamide and propane-1, 2-diol at different temperatures. J. Mol. Liq. 2013, 187, 260– 265,  DOI: 10.1016/j.molliq.2013.07.002
      36
      Experimenta5l studies on volumetric and viscometric properties of binary and ternary mixtures of N,N-dimethylacetamide, N-methylformamide and propane-1,2-diol at different temperatures
      Zarei, Hosseinali; Golroudbari, Sajad Akbari; Behroozi, Mahboobe
      Journal of Molecular Liquids (2013), 187 (), 260-265CODEN: JMLIDT; ISSN:0167-7322. (Elsevier B.V.)
      32569748K Excess molar volumes VmE, and viscosity η, of the ternary mixt. of N,N-dimethylacetamide (1) + N-methylformamide (2) + propane-1,2-diol (3) and their binary mixts. were obtained from d. ρ, and viscosity η, measurements over the entire mole fraction range at temps. (293.15 to 333.15) K. Neg. trend were obsd. for the VmE values of the binary mixts. in the whole compn. range except for N-methylformamide (2) + propane-1,2-diol (3) mixt. in the N-methylformamide rich region. Also, neg. VmE values were obsd. for the ternary mixt. except a few mole fractions in accordance with their binary mixts. Effect of rising temp. on the trend of the VmE values is not the same for the mixts. The viscosity values of the mixts. over the entire mole fraction range decrease with increasing temp. The results were interpreted based on the strength of specific interaction, size and shape of mols. The exptl. data of excess molar volumes were correlated with the Redlich-Kister and the Cibulka equations for the binary and ternary mixts., resp.
    37. 37
      Cano-Gómez, J. J.; Iglesias-Silva, G. A.; Cortez-Sánchez, L. D.; Castillo-Escobedo, M. T. Densities and Viscosities for Binary Liquid Mixtures of Butan-1-ol+ Propane-1, 2-diol + Butane-1, 2-diol and 2-Methylpropan-1-ol+ Propane-1, 2-diol,+ Butane-1, 2-diol from 298.15 to 333.15 K at 0.1 MPa. J. Chem. Eng. Data 2017, 62, 4252– 4265,  DOI: 10.1021/acs.jced.7b00621
      37
      Densities and Viscosities for Binary Liquid Mixtures of Butan-1-ol + Propane-1,2-diol, + Butane-1,2-diol and 2-Methylpropan-1-ol + Propane-1,2-diol, + Butane-1,2-diol from 298.15 to 333.15 K at 0.1 MPa
      Cano-Gomez, Jose J.; Iglesias-Silva, Gustavo A.; Cortez-Sanchez, Luis D.; Castillo-Escobedo, Maria T.
      Journal of Chemical & Engineering Data (2017), 62 (12), 4252-4265CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
      This paper presents densities and viscosities of binary mixts. of butan-1-ol (or 2-methylpropan-1-ol) with propane-1,2-diol, and butane-1,2-diol from 298.15 to 333.15 K at 0.1 MPa over the entire concn. range. A vibrating tube densimeter provides the densities while a glass capillary viscometer provides the efflux time which is related with the kinematic viscosity. Exptl. densities and viscosities of the pure components agree with data reported in the literature within an av. abs. percentage deviation of 0.03% and 1.16%, resp. The excess molar volumes and viscosity deviation calcd. from exptl. data present neg. deviations from ideality in the entire temp. range. The Redlich-Kister equation is used to represent the compn. behavior of excess molar volumes and the viscosity deviations. The Nava-Rios equation correlates our kinematic viscosity data within an overall av. abs. percentage deviation of 1.085% while the McAllister equation correlates the kinematic viscosity within 1.541%.
    38. 38
      Doghaei, A. V.; Rostami, A. A.; Omrani, A. Densities, viscosities, and volumetric properties of binary mixtures of 1, 2-propanediol+ 1-heptanol or 1-hexanol and 1, 2-ethanediol+ 2-butanol or 2-propanol at T=(298.15, 303.15, and 308.15) K. J. Chem. Eng. Data 2010, 55, 2894– 2899,  DOI: 10.1021/je900954y
      38
      Densities, Viscosities, and Volumetric Properties of Binary Mixtures of 1,2-Propanediol + 1-Heptanol or 1-Hexanol and 1,2-Ethanediol + 2-Butanol or 2-Propanol at T = (298.15, 303.15, and 308.15) K
      Doghaei, Asma Verdian; Rostami, Abbas A.; Omrani, Abdollah
      Journal of Chemical & Engineering Data (2010), 55 (8), 2894-2899CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
      Densities and viscosities for 1,2-propanediol + 1-heptanol or 1-hexanol and 1,2-ethanediol + 2-butanol or 2-propanol were measured over the whole compn. range at (298.15, 303.15, and 308.15) K and at atm. pressure. From the exptl. data, the excess molar volume, VmE, partial molar volumes, ‾Vm,1 and ‾Vm,2, and excess partial molar volumes, ‾Vm,1E and ‾Vm,2E, over the entire range of compn. were calcd. Viscosity deviations, Δη, were also obtained and showed neg. values for all investigated systems. These results were fitted to the Redlich-Kister polynomial equation to est. the binary interaction parameters. The viscosity data were correlated with equations of McAllister, and calcd. functions were used to explain the intermol. interaction between the mixing components.
    39. 39
      Anwar, N.; Riyazuddeen Effect of composition and temperature variations on thermophysical properties of binary and ternary mixtures of 1-ethyl-3-methylimidazolium ethylsulfate with 1-butanol and/or methanol. Fluid Phase Equilib. 2017, 437, 127– 139,  DOI: 10.1016/j.fluid.2017.01.019
      39
      Effect of composition and temperature variations on thermophysical properties of binary and ternary mixtures of 1-ethyl-3-methylimidazolium ethylsulfate with 1-butanol and/or methanol
      Anwar, Naushad; Riyazuddeen
      Fluid Phase Equilibria (2017), 437 (), 127-139CODEN: FPEQDT; ISSN:0378-3812. (Elsevier B.V.)
      The thermophys. properties, densities, ρ, speeds of sound, u and dynamic viscosities, η of pure ionic liq., 1-ethyl-3-methylimidazolium ethylsulfate, ([EMIM][ES]), and solvents 1-butanol, methanol and of their binary and ternary mixts. have been measured exptl. at a temp. range from (298.15-323.15) K, with an interval of 5 K and at pressure 0.1 MPa by using Anton Paar vibrating tube d. and sound velocity meter DSA 5000M and Lovis microviscometer 2000M. The excess molar volumes, VE, isentropic compressibilities, κs, molar isentropic compressibilities, Ks,m, excess molar isentropic compressibility, KEs,m, and viscosity deviations Δη have been calcd. using the exptl. ρ, u and η data at the same temp. range and pressure for [EMIM][ES] + 1-butanol/methanol binary systems and the VE, κs, excess isentropic compressibility, κEs and Δη for ternary [EMIM][ES] + 1-butanol + methanol system. The VE, κEs, KEs,m and Δη data for the studied binary/ternary systems have been fitted to Redlich-Kister equation. The variations in VE,κEs, KEs,m and Δη values with changes in compn. and temp. have been discussed in terms of hydrogen bonding, ion-dipole interactions and structural effects on mixing of ILs and solvents.
    40. 40
      Arce, A.; Rodil, E.; Soto, A. Volumetric and viscosity study for the mixtures of 2-ethoxy-2-methylpropane, ethanol, and 1-ethyl-3-methylimidazolium ethyl sulfate ionic liquid. J. Chem. Eng. Data 2006, 51, 1453– 1457,  DOI: 10.1021/je060126x
      40
      Volumetric and viscosity study for the mixtures of 2-ethoxy-2-methylpropane, ethanol, and 1-ethyl-3-methylimidazolium ethyl sulfate ionic liquid
      Arce, Alberto; Rodil, Eva; Soto, Ana
      Journal of Chemical & Engineering Data (2006), 51 (4), 1453-1457CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
      Densities, viscosities, refractive indexes, and speeds of sound at the temp. of 298.15 K and atm. pressure are reported for the binary and the miscible ternary mixts. of 2-ethoxy-2-methylpropane, ethanol, and 1-ethyl-3-methylimidazolium Et sulfate ionic liq. Excess molar volumes and viscosity, molar refraction, and isentropic compressibility changes of mixing have been calcd. from the phys. properties. The changes of mixing have been adequately fitted to the Redlich-Kister polynomial.
    41. 41
      Živković, E.; Kijevčanin, M.; Radović, I.; Šerbanović, S. P. Viscosities and refractive indices of binary systems acetone+ 1-propanol, acetone+ 1, 2-propanediol and acetone+ 1, 3-propanediol. Chem. Ind. Chem. Eng. Quart. 2014, 20, 441– 455,  DOI: 10.2298/CICEQ130305026Z
      41
      Viscosities and refractive indices of binary systems acetone + 1-propanol, acetone + 1,2-propanediol and acetone + 1,3-propanediol
      Zivkovic, Emila M.; Kijevcanin, Mirjana Lj.; Radovic, Ivona R.; Serbanovic, Slobodan P.
      Chemical Industry & Chemical Engineering Quarterly (2014), 20 (3), 441-455CODEN: CICEC2; ISSN:1451-9372. (Association of Chemical Engineers)
      Viscosities and refractive indexes of three binary systems, acetone + 1-propanol, acetone + 1,2-propanediol and acetone + 1,3-propanediol, were measured at eight temps. (288.15, 293.15, 298.15, 303.15, 308.15, 313.15, 318.15 and 323.15 K) and at atm. pressure. From these data, viscosity deviations and deviations in refractive index were calcd. and fitted to the Redlich-Kister equation. The viscosity modeling was done by two types of models: predictive UNIFAC-VISCO and ASOG VISCO and correlative Teja-Rice and McAlister equations. The refractive indexes of binary mixts. were predicted by various mixing rules and compared with exptl. data.
    42. 42
      Zafarani-Moattar, M. T.; Shekaari, H. Volumetric and Speed of Sound of Ionic Liquid, 1-butyl-3-methylimidazolium Hexafluorophosphate with Acetonitrile and Methanol at T = (298.15 to 318.15) K. J. Chem. Eng. Data 2005, 50, 1694– 1699,  DOI: 10.1021/je050165t
      42
      Volumetric and speed of sound of ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate with acetonitrile and methanol at T = (298.15 to 318.15) K
      Zafarani-Moattar, Mohammed Taghi; Shekaari, Hemayat
      Journal of Chemical and Engineering Data (2005), 50 (5), 1694-1699CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
      The authors report the d. (ρ) and speed of sound (u) data for 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) + methanol and ([BMIM][PF6]) + acetonitrile binary mixts. over the entire range of their compns. at T = (298.15 to 318.15) K. From these data, excess molar volume and isentropic compressibility deviation values have been calcd. and fitted to the fourth-order Redlich-Kister equation. The excess molar volume values (VE) for acetonitrile mixts. are more neg. than methanol mixts. Isentropic compressibility deviation values (Δκs) in methanol mixts. are more than acetonitrile mixts. The results have been interpreted in terms of ion-dipole interactions and structural factors of the ionic liq. and these org. solvents.
    43. 43
      Wang, J.; Tian, Y.; Zhao, Y.; Zhuo, K. A Volumetric and Viscosity Study for the Mixtures of 1-N-Butyl-3-Methylimidazolium Tetrafluoroborate Ionic Liquid with Acetonitrile, Dichloromethane, 2-Butanone And N N-Dimethylformamide. Green Chem. 2003, 5, 618– 622,  DOI: 10.1039/b303735e
      43
      A volumetric and viscosity study for the mixtures of 1-n-butyl-3-methylimidazolium tetrafluoroborate ionic liquid with acetonitrile, dichloromethane, 2-butanone and N, N - dimethylformamide
      Wang, Jianji; Tian, Yong; Zhao, Yang; Zhuo, Kelei
      Green Chemistry (2003), 5 (5), 618-622CODEN: GRCHFJ; ISSN:1463-9262. (Royal Society of Chemistry)
      The densities and viscosities for mixts. of 1-n-butyl-3-methylimidazolium tetrafluoroborate ionic liq. with acetonitrile, dichloromethane, 2-butanone and DMF have been detd. at 298.15 K. From these measurements, it was found that viscosities of the mixts. can generally be described by an exponential equation. Their densities are linear functions of the mass fraction of the ionic liq. in the mixts. These phys. properties can be predicted as a function of the concn. of ionic liq. provided that the properties for pure components are known. The excess molar volume VEm and the excess logarithm viscosities (ln η)E were calcd. and fitted to the Redlich-Kister polynomials. It is shown that the values of VEm are neg. but those of (ln η)E are pos. Surprisingly, the min. in VEm and the max. in (ln η)E are obsd. at about the same mole fraction of the ionic liq., x ≈ 0.3. The results are discussed in terms of the ion-dipole interactions between the cations of the ionic liq. and the org. solutes.
    44. 44
      González, E. J.; Alonso, L.; Domínguez, Á. Physical Properties of Binary Mixtures of the Ionic Liquid 1-Methyl-3-octylimidazolium Chloride with Methanol, Ethanol, and 1-Propanol at T = (298.15, 313.15, and 328.15) K and at P = 0.1 MPa. J. Chem. Eng. Data 2006, 51, 1446– 1452,  DOI: 10.1021/je060123k
      44
      Physical properties of binary mixtures of the ionic liquid 1-methyl-3-octylimidazolium chloride with methanol, ethanol, and 1-propanol at T = (298.15, 313.15, and 328.15) K and at P = 0.1 MPa
      Gonzalez, Emilio J.; Alonso, Luisa; Dominguez, Angeles
      Journal of Chemical & Engineering Data (2006), 51 (4), 1446-1452CODEN: JCEAAX; ISSN:0021-9568. (American Chemical Society)
      In this work, dynamic viscosities, densities, and speed of sound of 1-methyl-3-octylimidazolium chloride, [C8mim][Cl], with methanol, ethanol, and 1-propanol at T = (298.15, 313.15, and 328.15) K and refractive index at 298.15 K and 0.1 MPa have been measured over the whole compn. range. Excess molar volumes, isentropic compressibility deviations, and viscosity deviations for the binary systems from T = (298.15 to 328.15) K were calcd. These results were fitted to a Redlich-Kister equation to det. the fitting parameters and the root mean square deviations. As the ionic liq. has a negligible vapor pressure, its recovering from the title mixts. was realized by removal of the alc. component by vacuum at 343.15 K. Appreciable changes in the physicochem. properties of the recovered liq. were not obsd.
    45. 45
      Vogel, D. H. Das Temperatur-abhaengigkeitsgesetz der Viskositaet von Fluessigkeiten. Phys. Z. 1921, 22, 645
      45
      The law of the relation between the viscosity of liquids and the temperature
      Vogel, Hans
      Physikalische Zeitschrift (1921), 22 (), 645-6CODEN: PHZTAO; ISSN:0369-982X.
      The formula η1= η∞t-t1/t-t∞ is proposed, where ηt is the viscosity at any temp., t η∞ is the viscosity at another temp., t ∞, and tI is the temp. at which the viscosity is unity. It is said to give excellent agreement with all liquids, including water, mercury, and oils. Since only 3 detns. are required to obtain the consts. it is thought that the formula will be useful in oil technology.
    46. 46
      Fulcher, G. S. Analysis of Recent Measurements of the Viscosity of Glasses. J. Am. Ceram. Soc. 1925, 8, 339– 355,  DOI: 10.1111/j.1151-2916.1925.tb16731.x
      46
      Analysis of recent measurements of the viscosity of glasses
      Fulcher, G. S.
      Journal of the American Ceramic Society (1925), 8 (), 339-55CODEN: JACTAW; ISSN:0002-7820.
      If the abs. values of log10 viscosity obtained by Washburn, Shelton and Libman are brought into agreement with those of English the isothermal curves of log10 viscosity as a function of Na2O show no inflection up to 50% Na2O and may be represented by the equation: log10 η = -A + B × 105/(T - T0), where all 3 consts. vary with the compn. When CaO, MgO and Al2O3 are each substituted for Na2O in 6SiO2.2Na2O glasses there is a sharp bend in the curves between 840° and 1050°, designated aggregation temp. at which point the change of log10η per percent is a min., being 0.03-0.06 for CaO, 0.12 for MgO, 0.07 for Al2O3. The sharp bends suggest mol. aggregation but cannot be due to devitrification since it is not a function of time. The curves for the change of log10η in 4SiO2.2Na2O glasses are more complex when B2O3 is substituted for SiO2 than when substituted for Na2O.
    47. 47
      Tammann, G.; Hesse, W. Die Abhängigkeit der Viscosität von der Temperatur bie unterkühlten Flüssigkeiten. Z. Anorg. Allg. Chem. 1926, 156, 245– 257,  DOI: 10.1002/zaac.19261560121
      47
      The dependence of viscosity upon the temperature of supercooled liquids
      Tammann, G.; Hesse, W.
      Zeitschrift fuer Anorganische und Allgemeine Chemie (1926), 156 (), 245-57CODEN: ZAACAB; ISSN:0044-2313.
      The authors have measured the viscosity on supercooled liquids whose m. ps. ranged from-114° to +268°. The values of the viscosity η have been plotted against the temp. for each substance chosen. For the temp. interval chosen the curve is hyperbolic. The higher the m. p. the larger is the temp. range through which the viscosity values are found.
    48. 48
      Mauro, J. C.; Yueb, Y.; Ellisona, A. J.; Guptac, P. K.; Allana, D. C. Viscosity of Glass-Forming Liquids. Proc. Natl. Acad. Sci. U. S. A. 2009, 106, 19780– 19784,  DOI: 10.1073/pnas.0911705106
      48
      Viscosity of glass-forming liquids
      Mauro, John C.; Yue, Yuanzheng; Ellison, Adam J.; Gupta, Prabhat K.; Allan, Douglas C.
      Proceedings of the National Academy of Sciences of the United States of America (2009), 106 (47), 19780-19784CODEN: PNASA6; ISSN:0027-8424. (National Academy of Sciences)
      The low-temp. dynamics of ultraviscous liqs. hold the key to understanding the nature of glass transition and relaxation phenomena, including the potential existence of an ideal thermodn. glass transition. Unfortunately, existing viscosity models, such as the Vogel-Fulcher-Tammann (VFT) and Avramov-Milchev (AM) equations, exhibit systematic error when extrapolating to low temps. We present a model offering an improved description of the viscosity-temp. relationship for both inorg. and org. liqs. using the same no. of parameters as VFT and AM. The model has a clear phys. foundation based on the temp. dependence of configurational entropy, and it offers an accurate prediction of low-temp. isokoms without any singularity at finite temp. Our results cast doubt on the existence of a Kauzmann entropy catastrophe and assocd. ideal glass transition.
    49. 49
      Redlich, O.; Kister, A. T. Algebraic Representation of Thermodynamic Properties and the Classification of Solutions. Ind. Eng. Chem. 1948, 40, 345– 348,  DOI: 10.1021/ie50458a036
      There is no corresponding record for this reference.
    50. 50
      Tokuda, H.; Tsuzuki, S.; Susan, M. A. B. H.; Hayamizu, K.; Watanabe, M. How Ionic Are Room-Temperature Ionic Liquids? An Indicator of the Physicochemical Properties. J. Phys. Chem. B 2006, 110, 19593– 19600,  DOI: 10.1021/jp064159v
      50
      How Ionic Are Room-Temperature Ionic Liquids? An Indicator of the Physicochemical Properties
      Tokuda, Hiroyuki; Tsuzuki, Seiji; Susan, Md. Abu Bin Hasan; Hayamizu, Kikuko; Watanabe, Masayoshi
      Journal of Physical Chemistry B (2006), 110 (39), 19593-19600CODEN: JPCBFK; ISSN:1520-6106. (American Chemical Society)
      Room-temp. ionic liqs. (RTILs) are liqs. consisting entirely of ions, and their important properties, e.g., negligible vapor pressure, are considered to result from the ionic nature. However, we do not know how ionic the RTILs are. The ionic nature of the RTILs is defined in this study as the molar cond. ratio (Λimp/ΛNMR), calcd. from the molar cond. measured by the electrochem. impedance method (Λimp) and that estd. by use of pulse-field-gradient spin-echo NMR ionic self-diffusion coeffs. and the Nernst-Einstein relation (ΛNMR). This ratio is compared with solvatochromic polarity scales: anionic donor ability (Lewis basicity), ET(30), hydrogen bond donor acidity (α), and dipolarity/polarizability (π*), as well as NMR chem. shifts. The Λimp/ΛNMR well illustrates the degree of cation-anion aggregation in the RTILs at equil., which can be explained by the effects of anionic donor and cationic acceptor abilities for the RTILs having different anionic and cationic backbone structures with fixed counterparts, and by the inductive and dispersive forces for the various alkyl chain lengths in the cations. As a measure of the electrostatic interaction of the RTILs, the effective ionic concn. (Ceff), which is a dominant parameter for the electrostatic forces of the RTILs, was introduced as the product of Λimp/ΛNMR and the molar concn. and was compared with some phys. properties, such as reported normal b.ps. and distn. rates, glass transition temp., and viscosity. A decrease in Ceff of the RTILs is well correlated with the normal b.p. and distn. rate, whereas the liq.-state dynamics is controlled by a subtle balance between the electrostatic and other intermol. forces.
    51. 51
      Kapadi, U. R.; Hundiwale, D. G.; Patil, N. B.; Lande, M. K.; Patil, P. R. Studies of Viscosity and Excess Molar Volume of Binary Mixtures of Propane-1,2-diol with Water at Various Temperatures. Fluid Phase Equilib. 2001, 192, 63– 70,  DOI: 10.1016/S0378-3812(01)00621-5
      51
      Studies of viscosity and excess molar volume of binary mixtures of propane-1,2 diol with water at various temperatures
      Kapadi, U. R.; Hundiwale, D. G.; Patil, N. B.; Lande, M. K.; Patil, P. R.
      Fluid Phase Equilibria (2001), 192 (1-2), 63-70CODEN: FPEQDT; ISSN:0378-3812. (Elsevier Science B.V.)
      The excess molar volume VE, viscosity deviation Δη and excess Gibbs free energy of activation ΔG*E of viscous flow have been investigated from the d. and viscosity measurements of propane-1,2 diol (1) + water (2) over the entire range of mole fractions at 303.15, 308.15, 313.15 and 318.15 K. The results were fitted by Redlich-Kister equation. The system exhibited very large neg. values of VE due to increased interactions between unlike mols. or very large differences in the molar volumes of pure components at low temp.
    52. 52
      Anouti, M.; Vigeant, A.; Jacquemin, J.; Brigouleix, C.; Lemordant, D. Volumetric Properties, Viscosity and Refractive Index of the Protic Ionic Liquid, Pyrrolidinium Octanoate, in Molecular Solvents. J. Chem. Thermodyn. 2010, 42, 834– 845,  DOI: 10.1016/j.jct.2010.01.013
      52
      Volumetric properties, viscosity and refractive index of the protic ionic liquid, pyrrolidinium octanoate, in molecular solvents
      Anouti, Meriem; Vigeant, Annie; Jacquemin, Johan; Brigouleix, Catherine; Lemordant, Daniel
      Journal of Chemical Thermodynamics (2010), 42 (7), 834-845CODEN: JCTDAF; ISSN:0021-9614. (Elsevier Ltd.)
      Densities (ρ) and viscosities (η) of binary mixts. contg. the Protic Ionic Liq. (PIL), pyrrolidinium octanoate with 5 mol. solvents: water, methanol, ethanol, n-butanol, and acetonitrile are detd. at the atm. pressure as a function of the temp. and within the whole compn. range. The refractive index of all mixts. (nD) is measured at 298.15 K. The excess molar volumes VE and deviation from additivity rules of viscosities ηE and refractive index Δφn, of pyrrolidinium octanoate solns. were then deduced from the exptl. results as well as apparent molar volumes Vφi, partial molar volumes ‾Vm,i and thermal expansion coeffs. αp. The excess molar volumes VE are neg. over the entire mole fraction range for mixt. with water, acetonitrile, and methanol indicating strong hydrogen-bonding interaction for the entire mole fraction. In the case of longest carbon chain alcs. (such as ethanol and n-butanol) + pyrrolidinium octanoate solns., the VE variation as a function of the compn. describes an S shape. The deviation from additivity rules of viscosities is neg. over the entire compn. range for the acetonitrile, methanol, ethanol, and butanol, and becomes less neg. with increasing temp. Whereas, ηE of the {[Pyrr][C7CO2] + water} binary mixts. is pos. in the whole mole fraction range and decreases with increasing temp. the excess Gibbs free energies of activation of viscous flow (ΔG*E) for these systems were calcd. The deviation from additivity rules of refractive index Δφn are pos. over the whole compn. range and approach a max. of 0.25 in PIL mole fraction for all systems. The magnitude of deviation for Δφn describes the following order: Water > methanol > acetonitrile > ethanol. Results were discussed in terms of mol. interactions and mol. structures in these binary mixts.
    53. 53
      Workman, Jr., J.; Weyer, L. Practical Guide and Spectral Atlas for Interpretive Near-Infrared Spectroscopy; CRC Press, 2007.
      There is no corresponding record for this reference.
    54. 54
      Noda, I.; Ozaki, Y. Two-dimensional Correlation Spectroscopy – Applications in Vibrational and Optical Spectroscopy; John Wiley & Sons Ltd., 2004.
      There is no corresponding record for this reference.
    55. 55
      Haufa, K. Z.; Czarnecki, M. A. Effect of Temperature and Water Content on The Structure of 1,2-Propanediol and 1,3-Propanediol: Near-Infrared Spectroscopic Study. Vib. Spectrosc. 2009, 51, 80– 85,  DOI: 10.1016/j.vibspec.2008.10.013
      55
      Effect of temperature and water content on the structure of 1,2-propanediol and 1,3-propanediol: Near-infrared spectroscopic study
      Haufa, Krzysztof Zdzislaw; Czarnecki, Miroslaw Antoni
      Vibrational Spectroscopy (2009), 51 (1), 80-85CODEN: VISPEK; ISSN:0924-2031. (Elsevier B.V.)
      Effect of temp. and water content on the structure of 1,2-propanediol (12PD) and 1,3-propanediol (13PD) in the liq. phase has been studied by Fourier-transform near-IR (FT-NIR) spectroscopy. In addn., the spectra of both diols in CCl4 solns. at various concns. were measured. The exptl. spectra were analyzed by two-dimensional (2D) correlation approach and chemometric methods. The present results give no evidence that 12PD form the intramol. hydrogen bonding. In contrast, significant amts. of 13PD mols. in dild. CCl4 soln. is involved in the intramol. hydrogen bonding. At higher concns. the intramol. hydrogen bonds are broken and replaced by the intermol. ones. The structure of pure liq. propanediols is detd. by the intermol. hydrogen bonding. Unlike for monohydroxyl alcs., addn. of water to propanediols leads to faster temp.-induced breaking of the hydrogen-bonded assocs. However, variation of water content at const. temp. does not influence the structure of both diols. In this respect behavior of propanediols is similar to that of the monohydric alcs. The mols. of water in the mixts. are hydrogen bonded to the diols and act as a double proton donor. This bonding appears to be stronger than that in bulk water.

  • Supporting Information

    Supporting Information

    The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acsomega.3c03457.

    • Fitted parameters (A, B, T0) and corresponding fitting coefficient (R2) of the various equations for the viscosities; coefficients of the Redlich–Kister equation (Ai); activation enthalpy and activation entropy of viscous flow of the binary system of [C2mim]C2H5SO4 and propane 1,2-diol at different temperatures; eigenvalues and percentage of variance for the principal components of the binary mixture of [C2mim]C2H5SO4 and propane-1,2-diol of 0.1001 to 0.8911[C2mim]C2H5SO4 mole fraction; and synchronous and asynchronous 2D NIR correlation spectra calculated from the temperature-dependent spectral changes and loadings and scores for the PC1, PC2, PC3, and PC4 of the temperature-dependent NIR spectra of the binary mixture of [C2mim]C2H5SO4 and propane-1,2-diol at 0.1011–0.8911 [C2mim]C2H5SO4 mole fraction in the range of 6000–7500 cm–1 (PDF)


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