Ionic Liquid as Green Solvent for Leaching of Polycyclic Aromatic Hydrocarbons from Petroleum Source Rock

Microwave-assisted extraction of polycyclic aromatic hydrocarbons (PAHs) from petroleum source rock using ionic liquids was investigated and the conditions for optimum yields of the analytes were determined. Three ionic liquids showed similar extraction efficiencies and for further work 1-butyl-3-methylimidazolium bromide (BmimEr) was selected. The results showed that concentration and extraction temperature have significant effects on extraction yields of the PAHs. The 3.0 M ionic liquid solution was the best concentration for extraction of the PAHs. The highest yields of PAHs were obtained at an extraction time of 30 min. The optimum temperature for microwave-assisted ionic liquid extraction of all the PAHs from petroleum source rock was 100 degrees C. The results also show that microwave-assisted ionic liquid extraction is more efficient than accelerated solvent extraction and Soxhlet extraction. This study showed that microwave-assisted ionic liquid extraction (MAILE) is an efficient green analytical sample preparation technique for geochemical evaluation of petroleum source rock.