Patent ID: 8431743
Filing Date: 2013-04-30
Classification: C07C

Abstract:
1. A process for preparing acrylic acid by heterogeneously catalyzed partial gas phase oxidation of propylene, comprising: a) in a first reaction stage, subjecting propane to a heterogeneously catalyzed dehydrogenation in the presence of and/or with exclusion of oxygen to obtain a product gas mixture 1 comprising propane and propylene, and b) optionally, removing and/or converting to other compounds a portion of the constituents, other than propane and propylene, present in the product gas mixture 1formed in the first reaction stage to obtain a product gas mixture 1′ from product gas mixture 1, and c) in a second reaction stage, subjecting product gas mixture 1 and/or product gas mixture 1′, as a constituent of a starting reaction gas mixture (2- d) optionally, lowering the temperature of the product gas mixture (2- e) in a third reaction stage, subjecting product gas mixture (2- f) removing acrylic acid in a separating zone A from product gas mixture (3-