Heterogeneously catalyzed gas-phase partial oxidation of acrolein to acrylic acid, used to produce polymers for adhesives, involves using active multimetal oxide material containing e.g. molybdenum and vanadium

摘要

A heterogeneously catalyzed gas-phase partial oxidation of acrolein to acrylic acid over a catalytically active multimetal oxide material which contains the elements molybdenum and vanadium, tellurium or antimony, and elements consisting of niobium, tantalum, tungsten or titanium, whose X-ray diffraction pattern has no reflections with the peak position 2 theta = 50 +/- 0.30 but has reflections whose peaks are at specified diffraction angles. Heterogeneously catalyzed gas-phase partial oxidation of acrolein to acrylic acid over a catalytically active multimetal oxide material which contains the elements molybdenum and vanadium, tellurium or antimony, and elements consisting of niobium, tantalum, tungsten or titanium, whose X-ray diffraction pattern has no reflections with the peak position 2 theta = 50 +/- 0.30 but has reflections h, i and k whose peaks are at the diffraction angles (2 theta) 22.2 +/- 0.5 degrees (h), 27.3 +/- 0.50 (i) and 28.2 +/- 0.50 (k). The reflection (h ) is the one with the strongest intensity within the X-ray diffraction pattern and having a full width at half height of not more than 0.50; the intensity (Pi) of the reflection (i) and the intensity (Pk) of the reflection (k) fulfill the relationship that R is 0.65-0.85, where R is the intensity ratio defined by the formula R = Pi/(Pi + Pk); and the full width at half height of the reflection (i) and of the reflection (k) is in each case at most 10. The catalytically active multimetal oxide material is of formula (I). Mo1VaM1bM2cM3dOn (I). M1 = element(s) from the group consisting of Te and Sb; M2 = element(s) from the group consisting of Nb, Ti, W, Ta and Ce; M3 = element(s) consisting of Pb, Ni, Co, Bi, Pd, Ag, Pt, Cu, Au, Ga, Zn, Sn, In, Re, Ir, Sm, Sc, Y, Pr, Nd or Tb; a = 0.01-1; b = 0-1; c = 0-1; d = 0-0.5; n = number that is determined by the valency and frequency of the elements other than oxygen in formula (I).