Magnetically separable polyoxometalate catalyst for the oxidation of dibenzothiophene with H2O2

► Two H3PW12O40-functionalized Fe3O4 magnetic nanoparticles of Fe3O4-PEI-PW12O40 and Fe3O4-SiO2-NH2-PW12O40 were synthesized. ► Selectivity oxidation of dibenzothiophene to dibenzothiophene sulphone and dibenzothiophene sulfoxide was studied. ► The catalyst could be easily separated from the reaction system by adding a magnet and reused for several times.