Application Of Accelerated Solvent Extraction On Extracting Chloroform Bitumen Of Source Rocks

In this thesis, the results of a study on the application of accelerated solvent extraction technique to the extraction of extractable organic matter of source rock with ASE200 are discussed. The study focused on sample preparation techniques, equipment operation condition optimization, and data validation.Very comparable results can be achieved qualitatively and quantitatively by extracting the extractable organic matter from source rocks with accelerated solvent extraction and the traditional extraction methods, including soxhlet extraction, microwave extraction, shaking extraction and ultrasonic extraction. The comparative experiments show that the accelerated solvent extraction method has apparent advantages comparing to the other methods, demonstrating that the accelerated solvent extraction method can be effectively used in analytical organic geochemistry. It is operation automatic, solvent saving and environment friendly. It makes extraction much simple, quick, effective and safe. Especially, the extract yields conducted with accelerated solvent extraction method are of very good repeatability.According to the results of a serial test experiments, the optimized extraction conditions for extracting organic matter from source rocks with ASE200 accelerated solvent extraction is suggested: temperature, 110℃; pressure, 1500 psi; heating time, 5 min; static time, 5 min; flush volume, 60% cell volume; purge time, 60 sec; cycles, 2.Compare to soxhlet extraction, accelerated solvent extraction consumes one third of solvent and takes only 1% time for one run extracting the extractable organic matter from source rock with chloroform. It achieves very good extraction results with the standard deviation of extract yields 0.2% and the relative standard deviation 2.6% (n=10). Additionally, the bulk chemical composition of the chloroform bitumen obtained with accelerated solvent extraction is also very close to those obtained with soxhlet extraction, microwave extraction, shaking extraction and ultrasonic extraction.The GC-MS analytical results of the aliphatic and aromatic fractions of the extracts of six source rocks obtained with accelerated solvent extraction and soxhlet extraction separetly show very good consistence with each other for the molecular geochemical parameters of normal alkanes, terpenoids, steranes, and armotics, including distribution pattern of compounds and biomarker geochemical parameters, suggesting that accelerated solvent extraction tecnology can be successfully applied to the pretreatment of source rock for molecular organic geochemistry analyses.