Changes in structure of coal liquefied pitch during liquid-phase carbonization process
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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.
KeywordsCoal 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).
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Conflict of interest
The authors declare that they have no conflict of interests.
- 4.Luo WJ, Lan XZ, Song YH, Fu JP (2013) Research progress on utilization of coal liquefaction residue. Mater Rev 27(6):153–157Google Scholar
- 6.Gu XH, Shi SD, Zhou M (2006) Study on the molecular structure of asphaltene fraction from the Shenhua coal direct liquefaction residue. J Chin Coal Soc 31(6):785–789Google Scholar
- 7.Zhong JL, Li WB, Shi SD, Zhu XS (2012) Solvent extraction research on organic matter in direct coal liquefaction residue. J Chin Coal Soc 37(2):316–322Google Scholar
- 24.Manoj B, Kunjomana AG (2012) Study of stacking structure of amorphous carbon by X-ray diffraction technique. Int J Electrochem Soc 7:3127–3134Google Scholar
- 25.Zhu YM, Zhao XF, Gao LJ, Cheng JX, Lv J, Lai SQ (2017) Quantitative study of the microcrystal structure on coal based needle coke with curve-fitted of XRD and Raman Spectrum. Spectrosc Spectr Anal 37(6):1919–1924Google Scholar