Preparation of Fe/Zr-SBA-15 catalyst and its oxidative desulfurization performance

To improve the oxidative desulfurization performance, the modified SBA-15 (Fe/Zr-SBA-15) with different Fe/Zr molar ratios were synthesized by direct hydrothermal method. The samples were characterized by XRD, N₂ adsorption and desorption, TEM and UV-vis. Zr was incorporated into the framework of SBA-15. Apart from little aggregated iron oxides, most of the Fe species were well dispersed in Fe/Zr-SBA-15. The influence of the reaction temperature, amount of oxidant and dosage of catalyst on the conversion of DBT were investigated using Fe/Zr-SBA-15-1.0 as catalyst, H₂O₂ as oxidant and acetonitrile as extractant. The removal rate of DBT reached 97.1% under the conditions of reaction temperature 50 ℃, O/S molar ratio of 4 and catalyst dosage of 6 g/L. The synergistic effect of Fe and Zr played important role, with Fe^{3 +} acting as the oxidation activity center and Zr^{4 +} as the center of adsorption. In addition, the removal rate of DBT could still reach 91.3% after 4 cycles and Fe/Zr-SBA-15 showed good stability.