EFFECT OF PREPARATION METHOD ON THE DISPERSION AND ACTIVITY OF V2O5-AL2O3 CATALYSTS

Al2O3-supported 12 wt% V2O5 catalysts were prepared by physically grin ding both the oxides (solid-solid wetting) and by wet impregnation tec hniques. The physical mixtures (PM) were treated under two different c onditions-calcination in the presence of dry oxygen and wet oxygen. Th e catalysts were characterized by x-ray diffraction, scanning electron microscopy, electron spin resonance and oxygen and carbon dioxide che misorptions. Vanadia dispersion of the physical mixture calcined in th e presence of wet oxygen was found to be very similar to that of the V 2O5/Al2O3 catalyst prepared by the standard impregnation method. Metha nol partial oxidation activities of these catalysts were also comparab le.