| 摘要 |
<p>PURPOSE:To obtain maleic anhydride in high catalytic activity, in high conversion ratio and in high selectivity by using a specific orthophosphoric acid-based catalyst and subjecting butane to vapor-phase catalytic oxidation with molecular oxygen. CONSTITUTION:Butane is subjected to vapor-phase catalytic oxidation with molecular oxygen by using a catalyst which is a mixture of orthophosphoric acid-hydrogen vanadyl of the formula VOHPO4.0.5H2O and bivalent metal orthophosphate of the formula M3(PO4)2.nH2O (M is bivalent metal of Mg, Ca, Ba, Mn, Fe, Co, Ni, Cu or Zn; (n) is number of coordinated water differs depending upon preparation temperature) and is prepared by burning the mixture having the atomic ratio of M/V of 0.003-0.5 at 300-400 deg.C to give a catalyst and pretreating the catalyst in an inert gas or a mixed gas of a molecular oxygen-containing gas at 350-700 deg.C to give the objective maleic anhydride.</p> |
