饱和烃经5分子筛络合前后单体烃碳同位素分析对比研究

Comparison of Carbon Isotopic Composition of the Saturated Hydrocarbons before and after Complexation 5 Molecular Sieve

通过对自配标准样品(正构烷烃)进行5分子筛吸附试验,测定了用5分子筛吸附法分离前后正构烷烃、异构烷烃和环烷烃碳同位素值,探讨试验前后碳同位素值的变化。尽管实验过程中样品经过85℃长时间加热回流及吸附样品的5分子筛用氢氟酸酸化处理,但实验结果经仪器检测,证明该方法对正构烷烃碳同位素值影响因素不大。本文还介绍了原油和煤可溶有机质中饱和烃络合前后的单体烃碳同位素分析方法。并在前人工作的基础上,改进采用微型索氏抽提加热回流实验装置,既提高了样品的回收率,也减少了样品中轻组分的损失。

In order to find the difference of the isotopic composition of different organic compounds before and after complexation, the autogamy standard sample is performed by A molecular sieve adsorption to study the variation of the isotope compositions of n-alkanes, isoalkanes and cyclanes. Although samples were in a hot reflux for a long time at 85℃ in the experiment, and 5A molecular sieve of the adsorbed sample was acidized by hydrofluoric acid, the analytical method was tested to have little influence on carbon isotopic composition of the saturated hydrocarbons before and after complexation. This paper also discussed the method to analyze the individual hydrocarbon isotopic composition from crude oil and coal rock samples. On the basis of the previous work, the mini-sized Soxhlet extraction set with a hot reflux device is adopted to enhance the recovery of samples and diminish the loss of light components in the tested samples.