Removal of refractory organosulfur compounds via oxidation with hydrogen peroxide on amorphous Ti/SiO2 catalysts

Abstract

Efficient removal of benzothiophene (BT), dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (DMDBT) has been successfully achieved via oxidation with hydrogen peroxide in liquid phase using an amorphous silica-loaded titanium oxide catalyst. Both BT and DBT are easily oxidized to the corresponding sulfones, however in the case of DMDBT the steric hindrance of the alkyl groups makes the approach of the S-atom to the catalyst active centre (an isolated Ti(IV) species) difficult and therefore its reactivity is inhibited. The concentration of the organosulfur compound, the H2O2 concentration and the nature of the solvent play a key role in the rate of S-removal.