Evaluation of different pretreatment methods before individual carbon and hydrogen isotope analysis of crude oil

摘要

This study presents the difference in gas chromatograms and stable isotope values of hydrocarbon compounds after different pretreatment methods including both traditional column chromatography (TCC) and solid phase microextraction (SPME) separation. The results were as follows: (1) Except for condensate oil, the gas chromatography of analyte obtained by the two-methods shows distinctively different characteristics. (2) We did not observe significant carbon and hydrogen isotope fractionation for the same sample after it was treated by the two methods. (3) When conducting compound-specific isotope analysis (CSIA) of crude oil, we can combine two methods to achieve the isotope analysis and obtain more abundant geochemical information.