The effect of zirconia and niobia supports on the catalytic activity of surface VOx species in total oxidation of model volatile organic compounds

Samples of the catalysts containing 0.5, 5.0 and 40 mol.% of V2O5 supported on the ZrO2 and Nb2O5 oxides, prepared by wet impregnation, were characterized by XRD and EPR. Their catalytic activity was tested in methanol and acetone total oxidation. Vanadium bronze samples were synthesized as a reference. Redox properties of surface oxovanadium entities were investigated by adsorption of NO probe molecule and monitored by EPR. Strong effect of the support on surface architecture of the vanadium species and their catalytic performance was observed. The highest activity in total VOC oxidation (T50% = 205 °C for methanol and 230 °C for acetone) was observed for zirconia-supported catalysts containing 5.0 mol.% of V2O5. In all cases the niobia-supported catalysts were less active than the corresponding zirconia-supported samples.