Comb-grafted poly(vinyl phosphate)-based molybdovanadate heteropoly acid for efficient deep oxidative desulfurization using ionic liquid extractants under mild conditions

The development of simple and efficient desulfurization catalysts has garnered increasing attention in the field of desulfurization. In this study, comb-grafted polyethylene phosphomolybdenum-vanadium heteropoly acid catalysts (P-VPA-Mo m V n ) were synthesized via the bulk polymerization method. The structure and morphology of the catalysts were investigated by FTIR, GPC, 1 H NMR, XRD, XPS and SEM. By incorporating ionic liquid as an extractant, the P-VPA-Mo 10 V 2 demonstrates high activity in oxidative desulfurization, removing all DBT from the model oil with a low O/S molar ratio under mild conditions. It is noteworthy that when the reaction temperature is 30 °C, the O/S molar ratio is 3, and the reaction time is 60 min, the catalyst exhibits excellent recycling lifetime of 10 cycles without a significant decline in activity. The incorporation of the ionic liquid further enhances its extraction efficiency, indicating that the catalyst not only possesses a stable structure but also holds strong prospects for industrial application.