Oxidative desulfurization of DBT with H2O2 catalysed by TiO2/porous glass

Abstract

Aimed at ultra-deep oxidative desulfurization (ODS) of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) to control air pollution, we specially designed and prepared porous glass supported with TiO₂ nanoparticles acting as an amphiphilic catalyst. Hydrogen peroxide which is considered as the “green” oxidant was used, and for the extreme liquid–liquid phase ratio (usually larger than 1500) reaction system, a pore volume of 0.19 mL g⁻¹ of the catalyst provides enough space for the storage of hydrogen peroxide. The as-prepared catalyst offers a high interfacial surface area of 116.9 m² g⁻¹ and enhances the reaction by facilitating the mass transfer. The mono-dispersed TiO₂ exhibited good crystallinity. The mean diameter varied from 2.1 to 7.8 nm with the loading amount increasing from 1.27 wt% to 9.85 wt%. The catalyst showed high activity and good stability for producing ultra-clean fuels: 100% conversion was obtained within 2 min and the conversion just decreased from 100.0 ± 1.0% to 94.3 ± 0.6% after 5 cycles. Overall, this new reusable catalyst provided an alternative for highly efficient ultra-deep desulfurization in a green way.