Applications of Accelerated Solvent Extraction in Preparation of Poly-nuclear Aromatic Hydrocarbons in Oil and Gas Geochemical Exploration Samples

The method of oscillations-extraction was used to obtain target compounds for the analysis of geochemical exploration of oil and gas. The efficiency and precision of the results were unsatisfactory for practical samples when using this method. In order to improve the conventional method, accelerated solvent extraction technology was used to prepare poly-nuclear aromatic hydrocarbons samples. The experimental conditions (pressure, static extraction time and extraction temperature) are discussed and optimized with an extraction pressure of 8.3 MPa, extraction temperature of 80℃ and heating time of 5 min. Under the optimized experimental conditions, a comparison of the extraction efficiency of the accelerated solvent extraction with the conventional oscillation method was performed. The extraction efficiencies of 3 different samples were improved from 60.5% to 152.6%, and the satisfactory precision and stability were obtained with RSDs (n=7) of less than 4%. Accelerated Solvent Extraction technology is superior to traditional methods and gives more satisfactory results in accuracy and precision requirements. It can be applied to oil and gas geochemical exploration samples by pre-treatment processing.