Patent ID: 7026506
Filing Date: 2006-04-11
Classification: B01J,C07C

Abstract:
1. A process, comprising: preparing acrylic acid by heterogeneously oxidizing propene to acrylic acid in the gas phase with molecular oxygen over at least one multimetal oxide catalyst material present in a reaction zone, wherein the multimetal oxide catalyst material has a stoichiometry I where M M b is from 0.01 to 1, c is from>0 to 1, d is from>0 to 1 and n is a number which is determined by the valency and frequency of the elements other than oxygen in (I), wherein the X-ray diffraction pattern of the at least one multimetal oxide active material (I) has reflections h, i and k whose peaks are at the diffraction angles (2θ) 22.2±0.4° (h), 27.3±0.4° (i) and 28.2±0.4° (k), and