Supercritical Fluid Extraction of Organic Compounds in Rock Samples

The supercritical fluid extraction (SFE) behaviors for the extraction of organic compounds in rock samples are studied. The organic compounds in three different rock samples are extracted by pure supercritical CO2 at different conditions. The influences of pressure, temperature and time on extraction efficiency are evaluated. The extracts from SFE and Soxhlet extraction (SE) are analyzed by gas chromatographymass spectrometry. The results show: (1) when the totality of organic carbons in rock samples is high the results from two different extraction methods are in good agreement. (2) SFE is preferable for the extraction of saturated hydrocarbon compounds with low carbon content. And (3) SFE shows the inferiority in case of the totality of organic carbons in the rock samples is low.