A study of oxidative desulfurization of diesel catalyzed by acidic ionic liquid

With acidic ionic liquid as a catalyst and hydrogen peroxide as an oxidant, the deep desulfurization of hydrotreated diesel was conducted by oxidizing thiophenic sulfur into sulfone, which was then extracted by NMP. Effects of reaction temperature, reaction time and amount of catalyst on the reaction of oxidative desulfurization were also investigated. The optimal reaction conditions are as follows: 3mL oil sample (200×10-6 sulfur content), 1.5g acidic ionic liquid, 0.3mL hydrogen peroxide, reaction temperature of 25℃, reaction time of 3.5h and VNMP/Vdiesel of 1∶1. Under these conditions, good desulfurization ratio (86.7%) and lower sulfur content in diesel (25×10-6) were obtained. After the reaction, diesel oil and catalyst can be separated by simple decantation, and the activity of catalysts would not change obviously after recycling for 5 times.