One-Step Oxidative Desulfurization of Dibenzothiophene Using Cyclohexanone Peroxide in N-Alkyl-imidazolium-Based Ionic Liquid Extraction Systems

One-step oxidative desulfurization of dibenzothiophene (DBT) using cyclohexanone peroxide (CYHPO) was performed in the presence of N-alkyl-imidazolium-based ionic liquids (ILs). CYHPO is an oil-soluble oxidant and ILs are employed as extractants. The effect of the ILs, the molar ratio of CYHPO/S (O/S), volume ratio. (V-IL/V-model_oil), reaction time (T), and reaction temperature (t) were investigated in detail. The results showed that the desulfurization ability of the ILs followed the order [OMim]BF4 > [HMim]BF4 > [BMim]BF4, reversing the length of the alkyl group to the imidazolium ring. When IL [OMim]BF4 was used, O/S was 2 and V-IL/V-model_oil was 1:1, and 93.5% of DBT in the model oil was removed at 40 degrees C for 30 min. The desulfurization rate of gasoline was 70.8% under optimal conditions. IL ([OMim]BF4) could be recycled for five times without a significant decrease in activity.