| 摘要 |
<p>A method of making a vanadium phosphorus oxide (VPO) catalyst by precipitating from a 45-65 g/l solution of V4+ ions and V5+ ions a vanadium- and phosphorus-containing precipitate comprising a complex of formula VOHPO¿4? . 1/2H2O. The precipitate is calcined under an inert atmosphere to produce a VPO catalyst whose active phase is of formula (VO)2P2O9. Said solution comprises cations of at least two of Bi, Zr, Cr, Ce, Co, Mn, Mg and Mo such that the precipitate comprises 1-25 % by mass of said dopant metal cations in total, the balance being said complex. Each dopant metal forms 0.1-20 % by mass of the precipitate.</p> |
