关键词: 脱硫, 氧化, 萃取, 汽油, 柴油

Abstract: The desulfurization of oils using oxidation-extraction process does not need expensive equipment and the process is short. To solve the problems that the oxidation reaction rate is low and the quantity of oxidant is large, a new method is proposed to improve the reaction and mass transfer performance by adding a surfactant at a little amount into the reaction systems. A model system of dibenzothiophene DBT/octane, and oil products from a petrochemical company were taken as the working system respectively, with hydrogen peroxide as oxidant, phosphotungstic acid as oxidation catalyst, and acetonitrile/water azeotropic mixture as extractant. For the model system, the reaction time decreased from 24 h to 7 h at 50℃ by adding the surfactant of hexadecyltrimethyl ammonium bromide (CTAB) into the reaction systems, and the sulfur content was detected to be below 10′10-6 after only oxidation process. For light oils and diesel oils, the H2O2:oil volume ratio in the oxidation reaction could decrease from 1:1 to 1:25. The quantity of oxidant H2O2 decreased significantly, and the desulfurization rate after single-stage oxidation-extraction was above 50%, which was much higher than that of multi-stage extractions without oxidation.

Key words: desulfurization, oxidation, extraction, gasoline, diesel oil