Chromatographic Separation of Pristane and Phytane Stereoisomers and Its Geochemical Significance
详细信息
- 责任者：Xu Guanjun (Key Laboratory of Petroleum Geochemistry ; China National Petroleum Corporation ; Beijing 100083 ; China) ; Shuai Yanhua
- 刊名：Geochimica
- 出版年：2010
- 卷期：39(5)
- 关键词：烃类 ; petroleum products ; 原油 ; crude oil
- 页码：p.491-496
- 图表：2 illus., 7 refs.
- 分类号：1003
- issnNo：ISSN0379-1726
- isbnNo：CN44-1398/P
摘要
///Four crude oil samples,representing different depositional environments,were collected from Tuha,Daqing,Tarim and Jianghan oil fields,respectively.A cold seep carbonate sample from the South China Sea,was used as a reference due to its richness in crocetane(2,6,11,15-Tetramethylhexadecane) and 2,6,10,15,19-Pentamethylicosane(PMI).By using a 120 m long HP-5 column,phytane and its stereoisomer or crocetane could be well separated,and the resolution could be up to 0.9;pristane and meso-pristane were also separated at the same time.Stable carbon isotopic compositions of individual compounds of the saturated hydrocarbons were analyzed after the n-alkanes were removed by the molecular sieve method.The δ13C value of phytane at the mixed peak for well Guang33 is -28.4 ‰(PDB) and well TZ-10 is -33.9 ‰(PDB) while that for the cold seep carbonates sample is -47.8‰(PDB).Compared with the South China Sea carbonate sample,the presence of crocetane in the studied oils was deduced based on chromatographic retention time,mass spectrometry characteristics and stable carbon isotopic values.