Deep desulphurization of gasoline by catalytic oxidation using quaternary ammonium phosphotungstate as catalyst

Catalytic oxidation is an important means for deep desulfurization of oil products. In order to meet more stringent specifications of sulfur contents in oil products, studies on desulfurization methods with more selective and more active catalytic oxidation have become a hot subject. A quaternary ammonium phosphotungstate was prepared by hexadecyl trimethyl ammonium bromide and phosphotungstate. The prepared catalyst was characterized by FT-IR and SEM. The method of producing low sulfur gasoline was proposed using hydrogen peroxide as oxidant and the above catalyst. The effects of the extractants, oxidation and extraction conditions on desulphurization were examined. Under the conditions of gasoline 10mL, hydrogen peroxide 0.01mL, catalyst 0.0016g, oxidation reaction was performed at 30℃ with 60min. Using the multiplex solvent LJ-1 as the extractant and the solvent/oil ratio of 1, the sulfur content of gasoline is reduced from 179.3mg/L to 10.8mg/L at 20℃ with 15min. The desulphurization ratio reaches to 94.0%, which is higher than that of gasoline extracted directly without oxidation by 45.6%. The catalyst is high selective and low in dosage, which will be potential in gasoline desulphurization. The oxidized desulphurization effect is remarkable.