陕北低阶烟煤显微组分结构特征及分子结构模型

为了更好地利用我国丰富的低阶煤资源,以变质程度较低的陕北低阶烟煤镜质组、惰质组富集物作为研究对象,采用常规的煤质分析、傅立叶变换红外光谱、高分辨固体13C核磁共振、X射线衍射等分析表征手段,对样品结构进行全面分析,得到了陕北低阶烟煤显微组分分子结构特征及结构参数,建立了镜质组和惰质组的部分分子结构模型。结果表明,陕北低阶烟煤镜质组和惰质组氧含量均较高,硫含量很低,所选镜质组的芳碳率为0.634,平均缩合环数约为2.98个;惰质组的芳碳率为0.734,平均缩合环数约为3.15个;相对于镜质组,惰质组的缩合程度更高,芳核尺寸更大,排列也更加规则有序。今后低阶烟煤加工转化工艺的研究应从分子层面揭示其不同显微组分结构特征的差异性,为低阶烟煤清洁高效利用新工艺的开发奠定基础。

Structure characters and molecular structure models of low-rank bituminous coal macerals in northern Shaanxi

Vitrinite and inertinite concentrates,prepared by manual separation from Shanbei low rank bituminous coal,were analyzed using the ultimate analysis,FTIR,13C-NMR,and XRD.Molecular structure models of vitrinite and inertinite were proposed accordingly.Results indicate that the content of oxygen is higher,while sulfur is extremely low in both vitrinite and inertinite.Aromatic carbon ratio in vitrinite is 0.634 and the average number of condensation ring is 2.98,while they are 0.734 and 3.15 respectively in inertinite.The inertinite component exhibits higher condensation degree with larger aromatic nuclear size and more well-aligned structure than the vitrinite.Specification of relations between molecular structure and maceral group features from the viewpoint of molecular level will contribute to the high efficient and clean conversion of low-rank bituminous coals.