红外光谱法研究油页岩及干酪根的生油能力

Study on Oil Producibility from Oil Shale and Kerogen by Infrared Spectra

采用Lorentzian分峰拟合,A-C因子和含100%脂肪链的微晶石蜡为标准物质的方法对油页岩及去矿物油页岩干酪根红外吸收光谱进行了研究,分析了干酪根中各种烃的成分和含量.结果表明:油页岩及去矿物油页岩中有机质均为Ⅱ型干酪根;去矿物能使支链从干酪根主链上脱落,但去矿物程度不宜过大.随着去矿物程度加深,干酪根脂肪链含量、红外谱图中CH2与CH3吸收峰面积的比值和脂氢/芳氢面积比值先增大,后减小;油页岩经酸碱处理后,干酪根中脂肪链的含量可达到54.06%,CH2与CH3吸收峰面积的比值为7.11,脂氢和芳氢的面积比值为2.73.无机矿物质的去除使干酪根的生油潜力得到提高.

FT-IR spectra of oil shale and demineralized oil shale were studied by Lorentzian curve fitting and A-C factor,with the full-aliphatic-chain-bearing micritic paraffin taken as standard substance.The content and structure of various hydrocarbons in kerogen were analysed.The results showed that all the organic compounds in oil shale and demineralized oil shale were of the type-Ⅱ kerogen.Demineralization enables the aliphatic branches to be stripped from the backbone of kerogen,but the overdemineralization is unallowable because it will make the aliphatic chain content in kerogen,the CH2/CH3 ratio and the ratio of aliphatic C—H to aromatic C—H all increase then decrease.The aliphatic chain content in the type-Ⅲ kerogen is up to 54.06 %,while the values of CH2/CH3 ratio and the ratio of aliphatic C—H to aromatic C-H are 7.11 and 2.73,respectively.The removal of inorganic substance will improve the potential oil producibility of kerogen.