Effects of nitrogen compounds, aromatics, and aprotic solvents on the oxidative desulfurization (ODS) of light cycle oil over Ti-SBA-15 catalyst

Effects of nitrogen compounds, aromatics, and aprotic solvents on the oxidative desulfurization (ODS) of refractory sulfur compounds and light cycle oil over Ti-SBA-15 catalyst were studied in a batch or a continuous fixed-bed reactor with tert-butyl hydroperoxide (TBHP) as oxidant. The fresh and spent catalysts were characterized by BET, TGA, ICP-AES, and X-ray absorption spectroscopy. The nitrogen compounds were found to inhibit the ODS in the order: indole > quinoline > carbazole. The addition of aromatics solvent in feed gradually recovered the ODS activity for LCO. Moreover, the aprotic solvent significantly promoted the LCO ODS. These results were attributed to the high solubility of the oxidized S or N compounds in the aromatics and aprotic solvents, minimizing the deposit of oxidized product on the surface of the catalyst.