The VOx/SBA-15 has been found to be a better catalyst for the selective oxidation of methane to formaldehyde than SBA-15-supported Mo and W oxides. The influences of catalyst support and vanadium source on catalytic performances have been studied. The results show that SBA-15 is a better support than MCM-41 and Cab-O-Sil, and the catalyst with NH4VO3 as the precursor exhibits higher performances. The addition of phosphorus has been found to enhance slightly the selectivity to HCHO. Characterizations by XRD, N-2 physical adsorption, Raman spectroscopy and H-2-TPR suggest that the supported VOx species with loading amounts lower than 3 wt% be highly dispersed (probably as monomer) and contribute to the selective oxidation of methane to formaldehyde
