Superparamagnetic Mo-containing core-shell microspheres for catalytic oxidative desulfurization of fuel

Magnetic core-shell structured materials as carriers have received extensive attention in heterogeneous catalysis due to their unique magnetic responsively properties. Herein, we report a synthetic route to obtain magnetic core-shell microspheres by a sol-gel approach. The Fe3O4 (ca. 8 nm) is completely coated with SiO2 (ca. 15 nm) to prevent Fe3O4 from being oxidized in the reaction and the microspheres also show superparamagnetism, which allows the catalyst easy to separate. To explore their application, Mo-containing compound is loaded to their surface by impregnating and then calcined at different temperatures (100-800 °C). The obtained catalysts are used in oxidative desulfurization (ODS). The removal of DBT from model oil can reach 100% with calcination temperature at 400 °C and be recycled for at least five times without obvious decrease.

Dibenzothiophene (DBT) was extracted from the oil phase into the IL phase and then oxidized by the active peroxide species formed by magnetic catalysts and H2O2 to the corresponding sulfone.122