This study investigates the catalytic activity of TiO2/SiO2 in the oxidative desulfurization (ODS) of a model fuel containing dibenzothiophene (DBT) using hydrogen peroxide (H2O2) as an oxidant in the absence of UV irradiation. TheTiO2/SiO2 catalyst was synthesized through a novel method and thoroughly characterized by X-ray diffraction (XRD), FT-IR, nitrogen adsorption-desorption measurements, transmission electron microscopy (TEM), Field emission scanning electron microscopy (FESEM) and thermogravimetric analysis (TGA). Results revealed a great catalytic oxidative activity of the prepared catalyst in the removal of DBT regarding sulfur removal up to 99.4% within 20 min under optimum reaction conditions. The main factors affecting ODS process including catalyst dosage, temperature, O/S molar ratio and different oxidizing agents were evaluated to find optimum conditions. The catalyst was recoverable and desulfurization efficiency of the recovered catalysts showed no loss in activity after four times. A mechanism was also proposed to investigate the desulfurization process of DBT with the new catalyst in the presence of hydrogen peroxide. This work suggests a new and green method for the synthesis and characterization of an efficient catalyst (TiO2/SiO2) in the oxidative removal of refractory organosulfur compounds to achieve ultra-low sulfur fuels.

Keywords