Abstract
Selective oxidation Of toluene at room temperature was carried on vanadium containing molybdophosphoric acid supported on niobia catalysts rising t-butyl hydrogen peroxide (TBHP) as oxidant. The catalysts were characterized by FT-IR, X-ray diffraction (XRD), P-31 MAS NMR, Laser Raman spectroscopy and N-2 adsorption. The characterization data reveals (lie incorporation of vanadium and retention of intact Keggin ion on the support. The catalyst activity is related to the presence of vanadium in Keggin ion. The effect of TBHP-toluene concentration on the conversion and selectivity during toluene oxidation was also studied. A plausible reaction mechanism for the selective formation of benzaldehyde was proposed. The present catalyst is highly active, selective towards benzaldehyde and reusable with Out any appreciable loss in activity and selectivity. (C) 2009 Published by Elsevier B.V.