Patent ID: 8563774
Filing Date: 2013-10-22
Classification: B01J,B08B,C07C

Abstract:
1. A method for producing an unsaturated aldehyde and an unsaturated carboxylic acid through gas-phase catalytic oxidation of propylene, isobutylene, tertiary butyl alcohol, or methyl tertiary butyl ether with molecular oxygen in the presence of a catalyst comprising molybdenum, bismuth, and iron; which method comprises: (1) a washing step consisting of the following (a) and (b): (a) washing a surface of at least one device equipped in an apparatus for the production of the catalyst, to which a solid matter including molybdenum, bismuth and iron adheres, with a basic solution having a basic substance concentration of 1 to 6% by mass; (b) sequentially washing the surface of the device, which was washed with the basic solution, only with water to remove the basic solution; and (2) a step of producing the catalyst with the apparatus for the production of catalyst thus washed; and (3) conducting said gas-phase catalytic oxidation in the presence of the catalyst from step (2).