新阳炼焦煤结构的FTIR和XPS谱学表征

认知煤中主要元素的结构与赋存是获取煤结构参数的基础，对构建煤结构模型，研究煤的反应特性，合理利用煤炭资源具有重要意义。目前煤结构研究多是针对中低变质程度煤的，对炼焦煤结构研究较少，炼焦煤的结构模型尚未见报道。应用FTIR对新阳炼焦煤中羟基基团、脂肪结构、芳香结构、含氧官能团及杂原子结构进行谱学表征，通过XPS解析煤中氮和硫的赋存形式，掌握炼焦煤中主要元素的禀赋特征。结果表明： 新阳煤中与芳香环上的π电子形成的羟基π氢键是羟基的主要存在形式，多聚体是煤结构中缔合结构的具体表现；次甲基、甲基、亚甲基的含量依次增加，亚甲基和次甲基含量占煤中脂肪烃总量的82.05%，煤中烷基侧链较多；苯环二取代、苯环三取代是煤中芳香烃的主要结构，占芳香烃总量的86.74%；含氧官能团中，羟基和羰基是主要组成基团，羧基和醚基含量不足10%。新阳煤中硅的含量比较丰富，主要以Si-O-Si和Si-O-C的形态赋存。吡啶、吡咯和氮氧化物为氮的主要存在形式，绝大多数氮分布于煤分子结构单元的边缘；噻吩硫是煤中有机硫最主要的赋存形式，超过有机硫总量的60%，砜和亚砜的含量次之，硫醇和硫醚的赋存最少。

XPS and FTIR Spectroscopy Characterization about the Structure of Coking Coal in Xinyang

Structure and occurrence recognition for primary elements in coal are the foundations to acquire coal structural parameters and it is of great significance to construct a coal structure model,study reaction characteristics of coal and rationally utilize coal resources.At present,studies on the coal structure are most targeted at coals with a low-medium metamorphic degree.In comparison,the structure of coking coal is rarely studied and no structure model has been presented for it.In this paper,FTIR was adopted to carry out spectral characterization for hydroxyl polar groups,fat composition,aromatic structure,oxygen-containing functional group and miscellaneous atomic structure in Xinyang coking coal.The results demonstrated that,on the one hand,hydroxide radical π hydrogen bond formed by the Xinyang coking coal with π electrons in the aromatic nucleus was a main existing form of hydroxide radical;on the other hand,polymer was a concrete embodiment of associated structures in the coal.Besides,it also indicated that contents of methyne,methyl and methylene went up successively;and,methylene and methyne had a content occupying 82.05％in the total aliphatic hydrocarbon content in coal.The coal contained a great number of alkyl side-chains.Benzene ring-disubstitution and trisubstitution,with 86.74％taking in the total aromatic hydrocarbon content of coal,were primary structures of them.For an oxygen-containing functional group,while hydroxide radical and carbonyl were its principal composition groups,the content of carboxyl and ether group was less than 10％.In the Xinyang coal enriched with silicon,its occurrence lies in forms of Si-O-Si and Si-O-C.The main existing form of nitrogen included pyridine,pyrrole and oxynitride and most nitrogen distributed on edges of building blocks of coal molecules.As far as organic sulfur in coal was concerned,its primary existing form was thiophenic sulfur,the content of which exceeded 60％of the total organic sulfur content,followed by those of sulphone and sulfoxide.Occurrences of mercaptan and thioether were both at a minimum level.