The synthesis and comparative analysis of catalytic properties of Cu- and Mo-containing ethylpropylimidazolium derivatives immobilized on silica-series mineral supports have been performed. The oxidation of diethyl sulfide and methyl phenyl sulfide with oxygen and hydrogen peroxide in a hydrocarbon medium has been studied as a model process. The catalyst based on ethylpropylimidazolium polymolybdates is the most active and stable in the oxidation of methyl phenyl sulfide.