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Raman Spectroscopy as a Versatile Tool for Investigating Thermochemical Processing of Coal, Biomass, and Wastes: Recent Advances and Future Perspectives

  • Jun Xu
    Jun Xu
    State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
    More by Jun Xu
  • Qichen He
    Qichen He
    State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
    More by Qichen He
  • Zhe Xiong
    Zhe Xiong
    State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
    More by Zhe Xiong
  • Yun Yu
    Yun Yu
    State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
    More by Yun Yu
  • Shu Zhang
    Shu Zhang
    Joint International Research Laboratory of Biomass Energy and Materials, College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China
    More by Shu Zhang
  • Xun Hu
    Xun Hu
    School of Material Science and Engineering, University of Jinan, Jinan 250022, China
    More by Xun Hu
  • Long Jiang
    Long Jiang
    State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
    More by Long Jiang
  • Sheng Su
    Sheng Su
    State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
    More by Sheng Su
  • Song Hu
    Song Hu
    State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
    More by Song Hu
  • Yi Wang*
    Yi Wang
    State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
    *Email: [email protected]
    More by Yi Wang
  • , and 
  • Jun Xiang*
    Jun Xiang
    State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
    *Email: [email protected]
    More by Jun Xiang
Cite this: Energy Fuels 2021, 35, 4, 2870–2913
Publication Date (Web):December 21, 2020
https://doi.org/10.1021/acs.energyfuels.0c03298
Copyright © 2020 American Chemical Society

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    Abstract

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    Raman spectroscopy, as a rapid, high-precision, and nondestructive tool, can be used for analyzing the samples from gas to solid, from ex situ to in situ, from organic macromolecule to minerals. It has been demonstrated as a powerful tool for characterizing carbonaceous solid fuels and their thermal conversion products. This review provides a systematic overview of the application of Raman spectroscopy for investigating the entire thermochemical processing of coal, biomass, and wastes. After introducing the fundamentals of Raman spectroscopy, its application for characterizing the feedstock (raw coals, biomass, and wastes) is reviewed. Then, using the Raman spectroscopy for ex situ characterization of the products (char and ash) after reactions and in situ diagnostic during reactions are discussed. Besides, some potential advanced Raman spectroscopy techniques are further briefly introduced. Lastly, the challenges and prospects of using Raman spectroscopy to study thermochemical processes are discussed.

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    • Additional summary table for the comparison of RS to the IR, XRD, XRF, NMR, and SEM-EDS (PDF)

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