Carbon Letters

, Volume 29, Issue 1, pp 37–45 | Cite as

Changes in structure of coal liquefied pitch during liquid-phase carbonization process

  • Yaming Zhu
  • Xuefei ZhaoEmail author
  • Ji Yuan
  • Chunlei Zhao
  • Chaoshuai Hu
Original Article


Coal liquefied pitch (CLP) was prepared by the method of solvent extraction–hot filtration–distillation with the coal liquefied residue as the raw material. As one of the preconceived raw material to produce high-quality coal-based carbon material, the changes of structure of CLP during liquid-phase carbonization process have been detailed investigated in this study. Actually, FTIR and curve-fitted method were used to quantitative analyze the aromaticity index (Iar), the ratio of CH3/CH2, and basic functional groups (C=C, C=O, and C–O) of CLP and its liquid-phase carbonization products. Polarizing microscope, XRD and curve-fitted methods were used to characterize the microstructures of CLP and derived products. The results show that, branched chain and C=O group are the active reaction point in liquid-phase carbonization process. What’s more, 450 °C is a critical temperature point on the severe thermal polycondensation of CLP. The XRD and curve-fitted analysis of CLP and its liquid-phase carbonization products shows that, the stacking height (Lc), parallel layers (N), and the numbers of aromatic ring in each layer (n) are gradually larger with the improve of liquid-phase carbonization temperature.


Coal liquefied pitch Liquid-phase carbonization Structure 



This work was partially supported by the National Natural Science Foundation of China (U1361126), the Specialized Research Fund for the Doctoral Program of Higher Education (20132120110001), the Youth Fund of the Education Department of Liaoning Province (2017LNQN04), and the Youth Fund of University of Science and Technology Liaoning (2017QN06).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interests.


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Copyright information

© Korean Carbon Society 2019

Authors and Affiliations

  • Yaming Zhu
    • 1
    • 2
  • Xuefei Zhao
    • 1
    • 2
    Email author
  • Ji Yuan
    • 1
  • Chunlei Zhao
    • 1
  • Chaoshuai Hu
    • 1
  1. 1.Engineering Research Center of Advanced Coal Coking and Efficient Use of Coal Resources, Institute of Chemical EngineeringUniversity of Science and Technology LiaoningAnshanChina
  2. 2.Key Laboratory of Chemical Metallurgy Liaoning ProvinceUniversity of Science and Technology LiaoningAnshanChina

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