Lacunary phosphomolybdate PMo₁₁ supported on mesoporous KIT-6 as catalyst for oxidative desulfurization of model diesel

In this study, an efficient simultaneous extraction-oxidation catalytic system for deep desulfurization of a model fuel was investigated. For this purpose, mono lacunary phosphomolybdate (PMo₁₁) was synthesized. Then a series of PMo₁₁ catalysts were supported on mesoporous silica material (KIT-6). Structural characterization of the catalysts was performed by various techniques such as SEM, TEM, FT-IR, FT-Raman, ICP, BET and XRD. The results of the XRD and SEM analysis showed that the synthesized PMo₁₁ has a semi-crystalline structure. It was observed that the catalyst with 30% PMo₁₁ loading had the most catalytic activity on dibenzothiophene and benzothiophene removal in the oxidative desulfurization process. In this catalytic system, various conditions such as temperature, oxidizing agent value, catalyst amount, and extractant solvent type were varied and their effect on the reaction was evaluated. Under optimal conditions, dibenzothiophene was eliminated up to over 92.5%. The catalyst could be recycled and reused four times without significant reduction in its catalytic activity.