Activities of Vanadia-based Catalysts Prepared with Different Methods for Dehydrogenation of Isobutane to Isobutene

The V-Al-O catalysts prepared via impregnating,co-precipitation,hydrothermal,concentration,and hydrothermal-fluid drying,were characterized via XRD,TPR,TPD and ESR,etc.At the same time,they were compared with V2O5/γ-Al2O3 catalyst prepared via impregnation in the structure and dehydrogenation activities for dehydrogenation of isobutane to isobutene. It was found that the activities of the catalysts were obviously dependent on the preparation methods.The catalyst with large surface,surface enriched and welldispersed vanadia showed a higher dehydrogenation activity.Furthermore,the amount of Lewis acid on the surface of the catalyst was also an important factor to affect the selectivity of catalyst for isobutene.