岩石C6—C15轻烃定量分析方法研究

采用低沸点溶剂密封抽提技术和色谱"程序升温蒸发进样(PTV)切割反吹"分析技术,选用色谱内标法对岩石样品中C₆—C₁₅轻烃组分进行了定量分析研究.由于轻烃组分的不同挥发性,C₇以前的轻烃组分在前处理过程中受到了更多的损失,故在研究中以1-己烯做内标物来控制C₆—C₇间烃类物质的定量,以1-壬烯做内标物来控制C₇—C₁₅间(含C₇)烃类物质的定量.实验研究结果表明:方法回收率大于85%,岩石样品的重复性分析相对误差小于10%,方法稳定可靠.分析结果在提供C₆—C₁₅轻烃定量数据的同时还提供了轻烃指纹参数,因而其资料信息丰富,在油气田勘探和资源评价领域有一定的推广应用价值. 

RESEARCH ON THE QUANTITATIVE ANALYSIS METHOD OF C6-C15 LIGHT HYDROCARBON IN SOURCE ROCK SAMPLES

Supported by the low boiling-point solvent extraction technique and the gas chromatography technique of Programmed Temperature Vaporization(PTV) cut-out and back-flow,a quantitative research has been made on the C6C15 light hydrocarbon compounds in the source rock samples by means of an internal standard method.It is found that the light components before C7 lose more than other hydrocarbon components in the sample pre-processing process due to the volatility differences.So 1-hexenes was chosen as an internal standard reference to assure the quantitative analysis of C6 to C7,and 1-nonene was chosen as an internal standard reference to assure the quantitative analysis of C7 to C15(including C7).The results show high recovery(>85%) and good reproducibility(with RE<10%),indicating that this quantitative analysis method is stable and reliable.With this kind of analysis,not only the quantitative data of C6-C15 light hydrocarbons can be provided,the light hydrocarbon fingerprint parameters can also be offered.So it can bring rich geochemical information and has certain application values in the fields of oil and gas exploration and energy resource evaluation.