Selective oxidation of methane with hydrogen peroxide was catalyzed by several simple vanadium compounds in CH3CN.The reaction could afford formic acid as the major product.Vanadyl oxysulfate(VOSO4) was found to be an efficient catalyst.Specifically,the selectivity to formic acid of 70% at a methane conversion of 6.5% could be achieved over the VOSO4 catalyst under the reaction conditions of methane pressure 3.0 MPa and temperature 333 K for 4 h.The UV-Vis spectroscopic measurements revealed that the formation of V5+ species during the reaction might be vital for the methane activation.The reaction probably proceeded via radical mechanism.
