The Effect of Temperature on Molecular Structure of Medium-Rank Coal via Fourier Transform Infrared Spectroscopy
Abstract
:1. Introduction
2. Analytical Methods
2.1. Coal Samples
2.2. XRD Test
2.3. FTIR Testing and Processing
2.4. FTIR Structural Parameters
3. Results and Discussion
3.1. Coal Quality Analysis
3.2. Mineralogical Characterization
3.3. FTIR Spectroscopy Analysis
3.3.1. Peak Fitting and Analysis of Hydroxyl Structure
3.3.2. Peak Fitting and Analysis of C-Hal Structure
3.3.3. Peak Fitting and Analysis of Oxygen Functional Groups
3.3.4. Peak Fitting and Analysis of Aromatic Structure
3.3.5. Variation of Molecular Structure Parameters of Coal
3.4. Implications for Gasification
4. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Numbers | Moisture | Ash | Volatile Matter | C | H | O | N | S | C/H |
---|---|---|---|---|---|---|---|---|---|
R-303.15 K | 1.11 | 16.87 | 39.65 | 80.96 | 5.28 | 8.42 | 1.59 | 3.11 | 15.33 |
R-523.15 K | 4.19 | 17.70 | 34.12 | 72.30 | 3.09 | 19.81 | 1.57 | 2.65 | 23.40 |
R-623.15 K | 6.59 | 27.41 | 38.03 | 69.13 | 2.37 | 23.73 | 2.45 | 1.68 | 29.17 |
R-723.15 K | 6.06 | 24.00 | 39.25 | 70.12 | 1.99 | 23.18 | 2.52 | 1.66 | 35.24 |
Numbers | Kaolinite | Dolomite | Hematite | Pyrite |
---|---|---|---|---|
R-303.15 K | 86.2 | 11.7 | 0.2 | 1.9 |
R-523.15 K | 75.2 | 22.7 | 1.2 | 0.9 |
R-623.15 K | 70.4 | 26.6 | 2.4 | 0.6 |
R-723.15 K | 65.7 | 27.4 | 6.5 | 0.4 |
Functional Groups | R-303.15 K | R-523.15 K | R-623.15 K | R-723.15 K | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
PP | PA | P | PP | PA | P | PP | PA | P | PP | PA | P | |
AHG | 3518 | 1.49 | 17.57 | 3525 | 1.95 | 15.87 | 3512 | 3.66 | 16.56 | 3519 | 0.54 | 11.05 |
SHG | 3411 | 4.20 | 49.45 | 3413 | 2.52 | 55.34 | 3411 | 12.07 | 55.63 | 3426 | 3.07 | 63.69 |
EHG | 3266 | 2.09 | 24.62 | 3266 | 6.54 | 21.30 | 3305 | 0.10 | 0.48 | 3306 | 0.03 | 0.55 |
CHG | 3168 | 0.71 | 8.36 | 3178 | 0.92 | 7.49 | 3246 | 6.05 | 27.33 | 3180 | 1.32 | 24.71 |
Functional Groups | R-303.15 K | R-523.15 K | R-623.15 K | R-723.15 K | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
PP | PA | P | PP | PA | P | PP | PA | P | PP | PA | P | |
S-CH2 | 2856 | 2.13 | 35.60 | 2851 | 1.02 | 14.89 | 2856 | 1.41 | 23.13 | 2851 | 0.08 | 8.88 |
S-CH3 | 2870 | 0.02 | 0.27 | 2877 | 2.26 | 33.08 | 2879 | 0.53 | 8.69 | 2866 | 0.18 | 20.80 |
M-CH | 2893 | 0.70 | 11.71 | 2894 | 0.28 | 4.05 | 2895 | 0.24 | 3.95 | 2896 | 0.05 | 5.73 |
A-CH2 | 2919 | 2.21 | 37.06 | 2920 | 1.98 | 28.95 | 2918 | 2.49 | 40.77 | 2921 | 0.34 | 39.43 |
A-CH3 | 2952 | 0.92 | 15.36 | 2953 | 1.30 | 19.03 | 2957 | 1.43 | 23.46 | 2949 | 0.22 | 25.15 |
Functional Groups | R-303.15 K | R-523.15 K | R-623.15 K | R-723.15 K | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
PP | PA | P | PP | PA | P | PP | PA | P | PP | PA | P | |
Ash | 1015 | 0.19 | 0.54 | 1012 | 0.52 | 1.00 | 1010 | 2.71 | 3.32 | 1012 | 0.07 | 0.45 |
Alkyl ether (C–O) | 1034 | 1.07 | 3.10 | 1034 | 6.06 | 11.43 | 1035 | 14.77 | 18.33 | 1043 | 3.24 | 22.59 |
Aryl ether (C–O) | 1117 | 0.00 | 0.00 | 1117 | 3.36 | 6.34 | 1101 | 9.22 | 11.51 | 1111 | 1.64 | 11.44 |
Phenolic deformation C–O (stretching) | 1265 | 8.77 | 25.48 | 1253 | 1.82 | 3.50 | 1247 | 1.22 | 1.52 | 1189 | 0.28 | 1.93 |
Symmetric deformation –CH3 (bending) | 1385 | 8.93 | 25.92 | 1385 | 2.22 | 4.26 | 1399 | 2.94 | 3.66 | 1399 | 1.10 | 7.65 |
Aliphatic chains (–CH3, –CH2–) | 1435 | 7.24 | 21.16 | 1441 | 7.21 | 13.84 | 1443 | 4.64 | 5.79 | 1433 | 1.88 | 13.08 |
Aromatic nucleus (C=C) | 1599 | 7.84 | 22.89 | 1599 | 16.32 | 31.32 | 1597 | 29.12 | 36.34 | 1598 | 3.95 | 27.58 |
Conjugate (–C=O) | 1651 | 0.29 | 0.84 | 1659 | 12.35 | 18.20 | 1662 | 1.08 | 1.35 | 1650 | 0.63 | 4.40 |
Aromatic carboxyl (C=O) | 1693 | 0.03 | 0.08 | 1699 | 5.27 | 10.11 | 1717 | 14.68 | 18.17 | 1712 | 1.56 | 10.87 |
Functional Groups | R-303.15 K | R-523.15 K | R-623.15 K | R-723.15 K | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
PP | PA | P | PP | PA | P | PP | PA | P | PP | PA | P | |
DBR | 714 | 0.15 | 12.69 | 718 | 0.91 | 9.94 | 714 | 1.87 | 5.82 | 723 | 0.03 | 0.93 |
737 | 0.07 | 12.60 | 737 | 0.43 | 4.76 | 731 | 3.91 | 10.37 | 739 | 0.86 | 23.50 | |
TBR | 774 | 0.48 | 39.22 | 774 | 1.42 | 15.61 | 771 | 3.33 | 10.36 | 779 | 0.11 | 3.26 |
FSBR | 837 | 0.45 | 37.21 | 832 | 6.28 | 68.42 | 831 | 23.36 | 71.00 | 827 | 2.33 | 66.71 |
PBR | 891 | 0.07 | 5.51 | 891 | 0.12 | 1.26 | 889 | 0.22 | 0.68 | 889 | 0.20 | 5.59 |
Parameters | R-303.15 K | R-523.15 K | R-623.15 K | R-723.15 K |
---|---|---|---|---|
fH | 0.235 | 0.573 | 0.843 | 0.805 |
fC | 0.667 | 0.878 | 0.964 | 0.963 |
fa | 0.307 | 1.340 | 5.357 | 4.126 |
CH2/CH3 | 2.411 | 1.521 | 1.736 | 1.562 |
IR | 1.120 | 0.112 | 0.042 | 0.071 |
M | 0.996 | 0.756 | 0.665 | 0.717 |
DC | 0.234 | 0.561 | 1.122 | 0.896 |
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Wu, M.; Qin, Y.; Qin, Y.; Xu, N.; Feng, L. The Effect of Temperature on Molecular Structure of Medium-Rank Coal via Fourier Transform Infrared Spectroscopy. Materials 2023, 16, 6746. https://doi.org/10.3390/ma16206746
Wu M, Qin Y, Qin Y, Xu N, Feng L. The Effect of Temperature on Molecular Structure of Medium-Rank Coal via Fourier Transform Infrared Spectroscopy. Materials. 2023; 16(20):6746. https://doi.org/10.3390/ma16206746
Chicago/Turabian StyleWu, Meng, Yong Qin, Yunhu Qin, Naicen Xu, and Lele Feng. 2023. "The Effect of Temperature on Molecular Structure of Medium-Rank Coal via Fourier Transform Infrared Spectroscopy" Materials 16, no. 20: 6746. https://doi.org/10.3390/ma16206746
APA StyleWu, M., Qin, Y., Qin, Y., Xu, N., & Feng, L. (2023). The Effect of Temperature on Molecular Structure of Medium-Rank Coal via Fourier Transform Infrared Spectroscopy. Materials, 16(20), 6746. https://doi.org/10.3390/ma16206746