• 责任者：Xiang Tingsheng (School of Earth Eenvironment and Water Resources ; Yangtze University ; Jingzhou 434023 ; China) ; Wang Huimin
• 刊名：Geochimica
• 出版年：2013
• 卷期：42(6)
• 关键词：原油 ; crude oil ; 生物降解作用 ; biodegradation ; 辽河 ; Liaohe River
• 页码：p.567-575
• 图表：8 illus., 2 tables, 18 refs.
• 分类号：1003
• issnNo：ISSN0379-1726
• isbnNo：CN44-1398/P

     In the microbial degradation simulation experiment, a Liaohe oil sample was treated by the selected highly efficient degrading bacteria from the oil for different times to study the variation in molecular structure of crude oil with degradation degree. Group components of the oil before and after bacteria degradation were separated and the neutral nitrogen compounds and acidic compounds were obtained by further isolation. Then different fractions were analyzed using gas chromatography-mass spectrometry and infrared spectrometry. The results show that the concentration of n-monoacids （as methyl esters） in oil increase gradually with degradation time, and the C2s component of carboxylic acid in pentacyclic triterpenoid and moretanoids acid series increase too. Mild microbial degradation of oil has no significant effect on carbazole, methylcarbazole, and dimethyl carbazole compounds, while medium degradation has a certain impact on them. The infrared spectrograms of resins and asphaltenes show that bacteria are able to degrade these components in the crude oil. The length of side-chain in resins and asphaltenes shortens with microbial degradation. Aromatic compounds display less variation in condensation degree due to their strong resistance to microbial degradation. While the substituene is sensitive to microbial oxidation and produces acids and ethers, and the degree of oxidation increases with degradation. Therefore, it plays an important role in the exploration and development of crude oil to study the variation in structure and geochemical characteristics of non-hydrocarbon components in crude oil during microbial degradation.