Synthesis of P/W-coupled polyionic liquids for oxidative desulfurization of model oil

A novel PW-coupled polyionic liquid (1-n-butyl-3-vinylimidazolium phosphotungstate) (PBVImPW) was successfully synthesized and characterized by FT-IR, XRD, TG, ICP and CHN analysis. The prepared catalyst was applied in oxidative desulfurization processes of the model oil in the presence of H₂O₂. Several parameters including temperature, time, the amount of hydrogen peroxide and catalyst were investigated. PBVImPW is proved to be a highly efficient catalyst, and 99.4% benzothiophene conversion is achieved at reaction temperature of 50 ℃, n(H₂O₂)/n(S) ratio of 8, n(PBVImPW (P))/n(BT) ratio of 0.4 and reaction time of 150 min. There is not a significant decrease in the activity of the catalyst after being recycled four times.