中低变质程度煤显微组分结构的13 C-NMR研究

利用13C-NMR核磁共振技术对中低变质程度煤显微组分（镜质组和惰质组）的分子结构进行了研究，计算了5种煤9个显微组分的13C-NMR结构参数，获得了样品的结构特征及变化规律。结果表明，惰质组结构中芳构化程度要高于镜质组；脂碳数量则少于镜质组，芳环上的烷烃侧链也没有镜质组长；随着煤变质程度的提高，煤分子中芳构化程度不断提高，但惰质组的芳香度随变质程度变化的规律明显不如镜质组；在中低变质阶段，对煤化进程起主导作用的的是芳构化作用而不是环缩合作用，但在惰质组中脂碳断裂形成芳环的现象不明显。惰质组中含氧官能团的总量要低于同等变质程度的镜质组。

13 C-NMR analysis on different macerals of several low-to-medium rank coals

Structure characteristics of the different macerals of 5 low-to-medium rank coals were studied by means of 13 C-NMR. The molecular structure characteristics and parameters of the macerals were discussed. The result indicates that the aromaticity of inertinite is higher than that of vitrinite. There is less aliphatic hydrocarbon in inertinite. The side chain of hydrocarbon in inertinite is shorter than that in vitrinite. With the increase of coal rank, the aromaticity of both inertinite and vitrinite increases, but the aromaticity of inertinite increases more slowly than that of vitrinite. The aromatization (not ring-condensation) is dominant in the period of coalification of low-to-medium rank, and this phenomenon is more remarkable in vitrinite than that in inertinite. Additionally, the result of 13 C-NMR also shows that the total oxygen content in inertinite is lower than that in vitrinite.