Deep oxidative desulfurization of gas oil based on sandwich-type polysilicotungstate supported β-cyclodextrin composite as an efficient heterogeneous catalyst

Abstract

In this work, in order to obtain deep clean gas oil, a novel organic–inorganic hybrid (n-C4H9)4N)7H5Si2W18Cd4O68@β-cyclodextrin (abbreviated as [email protected]β-CD) composite was synthesized by supporting quaternary ammonium salt of sandwich-type polysilicotungstate on β-cyclodextrin ([email protected]β-CD) as an efficient catalyst for oxidative desulfurization (ODS) of gas oil. The successful composition of the materials explained by the formation of host–guest inclusion complex, which confirmed through FTIR, UV–vis, XRD, SEM, and EDX characterization analyses. Experimental results revealed that the levels of sulfur content and mercaptan compounds of gas oil lowered with 97% removal efficiency. Compared with the ODS treatment of gas oil, the [email protected]β-CD composite showed an outstanding catalytic performance for the oxidation of dibenzothiophene (DBT) in the prepared model fuel. The main factors that influence the desulfurization efficiency and the kinetic study of the ODS process were investigated. The prepared heterogeneous catalyst was found to give remarkable reusability for five runs without a discernible decrease in its activity. This study suggested the potential application of the [email protected]β-CD catalyst for removal of hazardous sulfur compounds from gas oil fuel.