Abstract: 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 well dispersed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.

Key words: V-Al-O catalyst, preparation method, isobutane, deh ydrogenation