The effect of N-containing compounds on oxidative desulphurization of liquid fuel

The oxidative removal of organic sulfur compounds from model fuel with H2O2 over Ti-containing molecular sieves in the presence of N-containing compounds had been studied. The effect of the types and amounts of nitrides on oxidative desulphurization were investigated. It has been shown that pyridine and pyrrole have adverse impact on the oxidation of thiophene and lead to the decrease of corresponding removal rate. The pyridine has stronger influence than pyrrole. Quinoline and indole have no impact on the final removal rate of thiophene. However, the two kinds of nitrides, as well as carbazole, have obvious impact on the oxidation removal of benzothiophene and 4,6-dimethyl dibenzothiophene. The effect of nitrides on oxidative desulphurization can be attributed to the strong adsorption of nitrides and their oxidized products on the active sites of catalysts. For pyridine and quinoline, which are basic nitrides, their adsorptions on catalysts are even stronger than that of sulfides.