Multi:metal oxide useful as catalyst esp. in gas phase oxidn. of acrolein to acrylic acid

摘要

Multimetal oxide compsn. of formula (I) is new: (A)p (B)q (I): A = Mo12VaX<1>bX<2>cX<3>dX<4>eX<5>fX<6>gOx (co-phase); B = X<7>12CuhHiOy (key phase); X<1> = W, Nb, Ta, Cr and/or Ce; X<2> = Cu, Ni, Co, Fe, Mn and/or Zn; X<3> = Sb and/or Bi; X<4> = Li, Na, K, Rb, Cs and/or H; X<5> = Mg, Ca, Sr and/or Ba; X<6> = Si, Al, Ti and/or Zr; X<7> = Mo, W, V, Nb and/or Ta; a = 1-8; b = 0.2-5; c = 0-23; d, g = 0-50; e = 0-2; f = 0-5; h = 4-30; i = 0-20; x, y = values depending on the valency and content of elements other than O; p, q = values other than O, with the ratio p/q = 160:1 to 1:1. The A and B fractions are each in the form of 30 zones, which differ in chemical compsn. from their local surroundings, and the relative distribution of the A and B zones is as in a mixt. of finely-divided A and finely-divided B. Also claimed are multimetal oxide compsns. of wolframite structural type, of formulae (II), (III), (IV) and (V): in (II), 1/(A+B+C+D+E) = 0.7-1.3; F = 0-1; and B+C+D+E = over 0 to 1. In (III), 1/(A+B+C) = 0.7-1.3; A, B, C all = more than O and B+C = at most 1; In (IV), 1/(A+B) = 0.7-1.3; A, B both = more than O and B = at most 1; In (V), 1/(A+C) = 0.7-1.3; A, C both - more than O and C - at most 1.