Zinc Substituted Keggin Type Polyoxometalate as an Effective Catalyst for the Oxidative Desulfurization of Dibenzothiophene by Hydrogen Peroxide as Oxidant
Abstract
One of the Keggin-type phosphotungstates, i.e. (TBA)5[PW11ZnO39].nH2O was synthesized and characterized by elemental analysis, X-ray diffraction, and infrared spectra, meanwhile their catalysis in an extractive catalytic oxidative desulfurization process was studied with acetonitrile as extractant and H2O2 as oxidant. The main factors affecting the desulfurization process were investigated, and optimized using sustainable systems conciliating successfully the liquid–liquid extraction. Results indicated an elevated catalytic activity with high to excellent yields for oxidation of dibenzothiophene to the corresponding polar sulfones which can be easily removed by solvent extraction or by adsorption by H2O2. The stability and reusability of the catalyst are very high, so this catalyst is suitable for the catalysis by hydrogen peroxide.