Improved process for the calcination/activation of v/p/o catalyst

摘要

An improved process for calcination and activation of a catalyst containing mixed oxides of vanadium and phosphorus (V/P/O) comprising the steps of calcining a hydrated V/P/O or V/P/O- SiO2 catalyst precursor at a temperature range of 375 DEG to 400 DEG C. for sufficient time to dehydrate said catalyst precursor while simultaneously and continuously controlling the oxygen level such as to maintain the Vox in the range of 3.825 to 4.175; and then activating the dehydrated catalyst precursor by further heating at a range of 340 DEG to 500 DEG C. in the presence of a gaseous atmosphere containing n-butane at a partial pressure not exceeding 0.20 atm while simultaneously and continuously controlling the oxygen level such as to maintain the Vox in the range of 3.95 to 4.15. Such a V/P/O catalyst is useful in the preparation of maleic anhydride from n-butane.