Aromatic sulfur compounds oxidation with H2O2 over fully coordinated and defect sites in Ti-beta zeolites: evaluation by density functional theory

The oxidative desulfurization mechanisms of aromatic sulfur compounds, including thiophene, benzothiophene, and dibenzothiophene, with H2O2 on fully coordinated and defective Ti sites on Ti-beta zeolites are investigated by means of density functional theory calculations. In this work, three current concerns are explored: First is the oxidation of sulfides into the sulfoxides and sulfones in the presence of H2O2; the second is the comparison between the sulfide oxidation mechanism on T5 and T2 defective sites in Ti-beta zeolites; and finally the comparison with the oxidation mechanism on fully coordinated Ti site on the Ti-beta zeolite. The model shows that T5 defect site in Ti-beta is the most catalytically active site for the oxidation of aromatic sulfides.