Abstract
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 (VIL/Vmodel 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 VIL/Vmodel oil was 1:1, and 93.5% of DBT in the model oil was removed at 40°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.
Notes
aTen milliliters of model oil with IL ([BMim]BF4) heated to 40°C for 2 hr.
bTen milliliters of model oil with CYHPO heated to 40°C for 2 hr.
cTen milliliters of model oil with CYHPO and IL ([BMim]BF4) heated to 40°C for 2 hr in two steps.
dTen milliliters of model oil with CYHPO and IL ([BMim]BF4) heated to 40°C for 2 hr in one step.