油页岩干酪根表面碳结构分析

Carbon Structure Analysis on the Surface of Oil Shale Kerogens

利用XPS技术对我国五个地区油页岩干酪根表面碳结构进行了定性和定量分析,揭示了碳元素在表面结构中的赋存形态和分布特性,并将XPS分析结果与文献中^(13)C NMR分析结果进行了对比。XPS结果表明,五个地区油页岩干酪根表面结构中均存在4种形态的碳:C-C/C-H、C-O/C-OH、C=O和O-C=O。其中,C-C/C-H的相对含量是最高的,达到75%以上。较低含量的C-C/C-H和较高含量的C-O/C-OH和O-C=O出现在MMK和LKK表面,表明二者沉积环境的氧化性要高于其它干酪根。对比结果表明,XPS和^(13)C NMR对干酪根中C-C/C-H均具有较好的分析能力,而在含氧碳官能团的分析上XPS具有更强的解析能力。

XPS was used to study the carbon structure for five oil shale kerogens in different regions, which reveals the forms and distribution of carbon structure in surface structure. The analysis results of XPS were also contrasted with that of 13C NMR in the literature. XPS results indicate that four forms of carbon were found on the surface of all kerogens：C-C/C-H, C-O/C-OH, C = O and O-C = O. The relative content of C-C/C-H was the highest among them, achieving more than 75%. A lower content of C-C/C-H and higher contents of C -O/C-OH and O-C = O appear on the surface of MMK and LKK, which means that the oxidability of sedimen- tary environment for the two kerogens is stronger than other kerogens. The comparison results show that XPS and 13C NMR both have a good analytical capability for C-C/C-H, while XPS has a stronger ability to analysis the carbon structure with oxygen.