Environmental Sustainability of Lighter Fluids

Lighter fluids are consumer products used only at a low-volume scale, representing a realizable goal of fossil fuel replacement by renewables. Physicochemical properties of four fossil-based conventional lighter fluids (Ronsonol, Zippo, Landmann, and Terracotta) and six selected biomass-based chemicals (γ-valerolactone, ethyl-levulinate, ethanol, n-butanol, γ-valerolactone 90% v/v and ethanol 10% v/v, and ethyl-levulinate 90% v/v and ethanol 10% v/v mixtures) as potential biomass-based lighter fluids were assessed. Assessments were carried out in terms of safety, toxicological, and environmental viewpoints, represented by a flash point, boiling point, vapor pressure values, and evaporation rates; oral toxicity measured on rats; and real ethanol equivalent values, respectively. Parameters were collected where available; in the absence of literature data, they were calculated or measured and then analyzed. Finally, multicriteria analysis based on the flash point, boiling point, vapor pressure, toxicity, and ethanol equivalent values revealed γ-valerolactone as a renewable substance, which can be a promising alternative to replace fossil-based lighter fluids because it was awarded as the first in the multicriteria evaluation by obtaining the highest value of the overall scores. In practical usage, however, ignition, combustion experiments, flue gas, and emission analysis are also required to underline its commercial use in the future.


S2 Model, Apparatus and Procedure of Flash point Determination
Closed cup flash points values were calculated for GVL 90% v/v and EtOH 10% v/v mixture and EL 90% v/v and EtOH 10% v/v mixture by using a model developed by Torabian and Sobati. 6ending index for component i, namely GVL, EtOH and EL was calculated according to Eq. S4, (S4)  ,  =  -1/  where X= 0.0382, as determined for alcohol-acetate binary mixtures and FP i is the closed cup flash point of component i in C, namely 96C and 90C for GVL and EL, respectively.Having the indices for the pure compounds and weighing them according to the molar fraction of each  ,  component, and could be calculated  , GVL 90% v/v and EtOH 10% v/v  , EL 90% v/v and EtOH 10% v/v according to Eq.s S5 and S6:  9 were also reported as OCFP of benzyl-alcohol. the initial heating rate is set at 15 °C/min; then reduced to 5.5°C/min when approaching the expected flash point;  moving the support flame over the liquid must be started 30°C below the expected flash point;  support flame must be moved towards the sample for every 2°C increase in temperature until the flash point is reached;  Flash point is the temperature at which ignition is detected when the ignition lever is inserted.

S3 Apparatus and Procedure of Evaporation Rate Determination
Evaporation rate was determined in a drying furnace at temperatures of 30°C, 40°C and 50°C.
Lowest temperature was set at 30°C agreeing that most commonly outdoor BBQs are carried out around this air temperature.On a sunny day charcoal can collect sunshine and be heated up, therefore 50°C was selected as the highest temperature for evaporation of LFs.LFs were poured into a Petri dish covering its whole surface.10.00 ± 0.1 mL was used for GVL, EL and their mixtures with ethanol, and 5.00 ± 0.1 mL for commercial LFs.After adjusting the temperature of the furnace, LFs in a premeasured Petri dish were placed into the furnace.Mass of the LFcontaining Petri dish was measured in every two minutes.Each experiment was repeated threetimes, and averages were taken into account during evaluation.Evaporation rate was calculated on the measured mass of LFs versus time.

5 a
replaced by 2-methyl-decane, b replaced by tridecane, c replaced by n-propyl-cyclohexane Vapor pressures of Terracotta and Landmann lighter fluids (represented as p 0 mixture ) were calculated according to Dalton equation, considering the weighted sum of each compound's vapor pressure: (S3)  0  = ∑    •  0  Where: p 0 mixture vapor pressure of lighter fluid [Pa] x i molar fraction of compound i in the lighter fluid [mol/mol] p 0 i vapor pressure of compound i [Pa]

Figure S- 1
Figure S-1 Cleveland type flash point measuring device

Figure S- 2 Figure S- 3
Figure S-2 Weighing scale, stopwatch and thermostat used for evaporation tests at 30, 40 and 50°C

Figure S- 4
Figure S-4 Junkers type calorimeter

Table S1
Components of Terracotta lighter fluid identified by GC-MS, relating Antoine constants and the calculated vapor pressures (p 0 ) of each compound a replaced by 2-methyl-decane, b replaced by tridecane Vapor pressure of a given component at given temperature was calculated according to different types of Antoine equations (S1 and S2): S3 S1

Table S2
Components of Landmann lighter fluid identified by GC-MS, relating Antoine constants and the calculated vapor pressures (p 0 ) of each compound

Table S 3 Molar fractions of compounds in GVL 90% v/v and EtOH 10% v/v mixture and EL 90% v/v and EtOH 10% v/v mixture
By substituting the related molar fractions (TableS3) and blending indices, closed cup flash points of binary mixtures could be calculated as 34 and 30C for GVL 90% v/v and EtOH 10% v/v mixture and EL 90% v/v and EtOH 10% v/v mixture, respectively.Flash point (FP) determination was executed on a Cleveland type flash point measuring device, which is suitable for determining the open-air flash point -so called open cup flash point (OCFP) -and ignition point of all flammable liquids and petroleum derivatives having a flash point