Deep oxidative desulfurization of dibenzothiophene with POM-based hybrid materials in ionic liquids

A series of POM-based hybrid materials: phosphotungstic acid supported ceria (HPW-CeO2) have been synthesized and characterized by X-ray diffraction (XRD), Thermogravimetric-differential scanning (TG-DSC) analysis, Scanning electron microscopy (SEM), FT-Raman, FT-IR, UV–vis, and BET analysis. Combined with [C8mim]BF4, the catalyst was very efficient on the removal of DBT by using H2O2 as the oxidant under mild reaction conditions, which could reach a sulfur removal of 99.4%. The amount of catalyst, O/S molar ratio, reaction time and temperatures were evaluated in detail, and the favorable operating condition was obtained as well as the kinetic study of substrates. The structure–activity relationship was systematically investigated. Oxidative desulfurization system could be recycled for ten times without significant decrease in activity. A mechanism was proposed to investigate the oxidation process of DBT.

Graphical abstract(A) Before oxidation, (B) during oxidation, (C) after oxidation and (D) catalytic oxidation process of DBT.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► POM-based hybrid materials were firstly combined with ionic liquids on the removal of DBT. ► The catalyst demonstrated high performance in the deep desulfurization. ► The mechanism and kinetic of oxidation desulfurization process was proposed. ► The structure–activity relationship reactivity of samples was systematically investigated.