陕北侏罗纪煤不同显微组分的分子结构特征

为查明陕北侏罗纪煤镜质组与惰质组大分子结构特征及差异，运用X射线衍射分析（XRD）、傅里叶红外光谱（FTIR）对煤的大分子结构、芳香烃、脂肪烃以及含氧官能团等进行表征，计算了原煤及不同煤岩组分分离物中红外光谱结构参数。结果表明，富镜煤的XRD谱图不对称性高于富惰煤，富惰煤芳香层片面网间距d002小于富镜煤；富惰煤的芳香度、La和Lc均大于富镜煤与原煤，前者芳香层片堆叠的有序程度及芳香环的缩合程度较大；富镜煤中苯环四取代含量最高，表明其缩合程度高并含有较多的支链；各煤样脂肪结构均以亚甲基为主，且具有较多的烷基侧链，而富惰煤中亚甲基含量相对较少，归因于脂族结构断裂程度不同；富惰煤呈现富碳、贫氢、少氧，高芳碳率、芳香度、缩合程度和成熟度，含有较多的C=O结构，生烃潜力较富镜煤弱。研究为煤炭清洁高效利用提供了科学依据。

Molecular structure characteristics of different macerals of Jurassic coal in northern Shaanxi Province

To find out the characteristics and differences of macromolecular structure between vitrinite and inertinite of Jurassic coal in northern Shaanxi，X-ray diffraction （XRD） and Fourier transform infrared spectroscopy （FTIR） were used to characterize the macromolecular structure，aromatics，aliphatic hydrocarbons and oxygen-containing functional groups of the coal.The structural parameters of the raw coal and the separations of different petrographical coal were calculated.The results showed that the asymmetry of XRD spectrum of vitrinite-rich coal is higher than that of inertinite-rich，and the one-sided network spacing d002of aromatic layer of inertinite-rich is less than that of vitrinite-rich coal.The aromaticity，La and Lc of inertinite-rich are higher than those of vitrinite-rich coal and raw coal，indicating that the stacking order of aromatic layers and the condensation degree of aromatic rings of inertinite-rich coal are relatively large.The highest content of benzene ring tetrasubstituted in vitrinite-rich coal indicates its high degree of condensation and contains more branched chains.The aliphatic structure of the series of coal samples is mainly methylene，which contains more alkyl side chains，but the content of methylene in inertinite-rich coal is relatively small，which may be related to the fracture degree of aliphatic structure in the separations of different coal and rock components.Inertinite-rich has the characteristics of rich carbon，poor hydrogen，less oxygen，high aromatic carbon rate，aromaticity，condensation degree and maturity，and contains more C=O structure，which shows that the hydrocarbon generation potential is weaker than vitrinite-rich coal.The research provides a scientific basis for the clean and efficient utilization of coal.