Effects of Parent Coal Properties on the Pyrolytic Char Chemical Structure: Insights from Micro-Raman Spectroscopy Based on 32 Kinds of Chinese Coals
Abstract
:1. Introduction
2. Experiments and Methods
3. Results and Discussion
3.1. The C-H Structures in Pyrolytic Chars
3.2. The Aromatic Rings in Pyrolytic Chars
3.2.1. Effects of Moisture in Parent Coal on the Aromatic Rings’ Structure
3.2.2. Effects of Ash in Parent Coal on the Aromatic Rings’ Structure
3.2.3. Effects of the Fixed Carbon Content in Parent Coal on the Aromatic Rings’ Structure
3.3. Relationship between the Comprehensive Coal Property Index and Pyrolytic Char Structures
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Band Name | Band Position, cm−1 | Description |
---|---|---|
R | 960-800 | C-C on alkanes and cyclic alkanes; C-H on aromatic rings |
SR | 1060 | C-H on aromatic rings; benzene (ortho-di-substituted) ring |
S | 1185 | Caromatic-Calkyl; aromatic (aliphatic) ethers; C-C on hydro-aromatic rings; hexagonal diamond carbon sp3; C-H on aromatic rings |
SL | 1230 | Aryl-alkyl ether; para-aromatics |
D | 1320 | D band on highly ordered carbonaceous materials; C-C between aromatic rings and aromatics with not less than 6 rings |
VR | 1380 | Methyl group; semi-circle breathing of aromatic rings; amorphous carbon structures |
VL | 1465 | Methylene or methyl; semi-circle breathing of aromatic rings; amorphous carbon structures |
GR | 1540 | Aromatics with 3–5 rings; amorphous carbon structures |
G | 1590 | Graphite ; aromatic ring quadrant breathing; alkene C = C |
GL | 1680 | Carbonyl group C = O |
2S | 2300 | Overtone of the band at 1150cm−1, Caromatic-Calkyl, C = O structures |
(2D)R | 2480 | Large aromatic rings system |
2D | 2670 | Overtone of the D band, C-C between aromatic rings, large aromatic rings system |
(2D)L | 2810 | C-H stretch of methyl and methylene, amorphous carbon structures |
D+G | 2925 | Combination of D band and G band, large aromatic rings system |
(2G)R | 3060 | Aryl C-H stretch vibration |
2G | 3180 | Overtone of the G band at 1590 cm−1, aromatic rings |
(2G)L | 3320 | Overtone of the peaks at 1670 cm−1, Carbonyl group C = O |
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Chen, D.; Ning, X.; Tang, W.; Xu, J.; Xu, K.; He, L.; Han, H.; Su, S.; Jiang, L.; Wang, Y.; et al. Effects of Parent Coal Properties on the Pyrolytic Char Chemical Structure: Insights from Micro-Raman Spectroscopy Based on 32 Kinds of Chinese Coals. Processes 2021, 9, 1575. https://doi.org/10.3390/pr9091575
Chen D, Ning X, Tang W, Xu J, Xu K, He L, Han H, Su S, Jiang L, Wang Y, et al. Effects of Parent Coal Properties on the Pyrolytic Char Chemical Structure: Insights from Micro-Raman Spectroscopy Based on 32 Kinds of Chinese Coals. Processes. 2021; 9(9):1575. https://doi.org/10.3390/pr9091575
Chicago/Turabian StyleChen, Dezhi, Xinyu Ning, Wen Tang, Jun Xu, Kai Xu, Limo He, Hengda Han, Sheng Su, Long Jiang, Yi Wang, and et al. 2021. "Effects of Parent Coal Properties on the Pyrolytic Char Chemical Structure: Insights from Micro-Raman Spectroscopy Based on 32 Kinds of Chinese Coals" Processes 9, no. 9: 1575. https://doi.org/10.3390/pr9091575