Li Na, Liu Quan-sheng, Zhen Ming, Zhao Bin, Feng Wei, Song Yin-min, Zhi Ke-duan, He Run-xia
Guang Pu Xue Yu Guang Pu Fen Xi. 2016 Sep;36(9):2760-5.
The combustion reaction of raw coals in the air was analyzed withThermal Gravimetric Analyzer 6300 and FTIR (Fourier Transform infrared spectroscopy). The raw coals came from three different sources which were SL lignite, SH bitumite and TT anthracite. The chars were prepared by fixed bed pyrolysis equipment in different reaction temperature. The overlapping peaks were fitted into some sub-peaks by Gaussian function. The aromatic index (R), aromatic structure fused index (D) and organic maturity index (C) were calculated through sub-peaks areas. It showed that three kinds of ignition temperature of SL, SH and TT were 299.3, 408.2 and 441.0 ℃ respectively. The peak temperature of maximum weight loss rate were 348.6, 480.5 and 507.0 ℃ respectively. With the increase of coal rank, both ignition temperature and peak temperature of maximum weight loss rate increased in some degree. The result showed that coal structure was very complex. Vibration absorption peaks of hydroxyl (—OH), aliphatic hydrocarbons (—CH2，—CH3), aromatic (CC), oxygen-containing functional group(CO, C—O) and other major functional groups could be observed in the infrared spectral curves of all samples. With the increase of pyrolysis temperature, infrared vibration absorption peaks of aliphatic hydrocarbons (—CH2—, —CH3) were gradually decreased. the stretching vibration peak of CO which was at 1 700 cm-1 almost disappeared after coked at 550 ℃. SL samples’ absorption peak area infrared curve of oxygen functional groups at 1 000～1 800 cm-1 was more complex. With the increase of coking temperature they changed more significantly compared with others. While peak position and peak intensity for aromatic CC absorption peaks of SH and TT did not change apparently when temperature was changing. Variation trends of main functional groups among three ranks of coals were obviously different with changes of R, D and C values.
采用热重分析仪6300和傅里叶变换红外光谱仪（FTIR）对原煤在空气中的燃烧反应进行了分析。原煤来自三个不同产地，分别是SL褐煤、SH烟煤和TT无烟煤。通过固定床热解设备在不同反应温度下制备半焦。利用高斯函数将重叠峰拟合为若干子峰。通过子峰面积计算芳香度指数（R）、芳环缩合指数（D）和有机成熟度指数（C）。结果表明，SL、SH和TT三种煤的着火温度分别为299.3、408.2和441.0℃，最大失重率的峰值温度分别为348.6、480.5和507.0℃。随着煤阶的升高，着火温度和最大失重率的峰值温度均有一定程度的升高。结果表明，煤的结构非常复杂。在所有样品的红外光谱曲线中都能观察到羟基（—OH）、脂肪烃（—CH2，—CH3）、芳香烃（CC）、含氧官能团（CO，C—O）等主要官能团的振动吸收峰。随着热解温度的升高，脂肪烃（—CH2—，—CH3）的红外振动吸收峰逐渐减弱。在550℃焦化后，位于1700 cm-1处的CO伸缩振动峰几乎消失。SL样品在1000～1800 cm-1范围内含氧官能团的红外曲线吸收峰面积更为复杂，随着焦化温度的升高，其变化比其他样品更为显著。而SH和TT的芳香烃CC吸收峰的峰位和峰强在温度变化时没有明显变化。随着R、D和C值的变化，三种煤阶煤中主要官能团的变化趋势明显不同。
