Patent attributes
As catalysts for producing aromatic amines by hydrogenating aromatic nitrites, there are disclosed (1) the catalyst comprising a metal catalyst component comprising Ni and/or Co and a specific amount of zirconia as a carrier component, which is prepared by drying, calcining and forming a precipitate produced by adding an aqueous solution containing soluble salts of the metal catalyst component and the carrier component to an aqueous alkali solution; and (2) the catalyst comprising the metal catalyst component and the carrier component, which is prepared by filtering a precipitate produced by adding an aqueous solution containing soluble salts of the metal catalyst component and the carrier component to an aqueous alkali solution; forming the precipitate without drying to obtain a formed product; and subjecting the formed product to drying and then calcining. These catalysts are free from breaking owing to rapid generation of methane and evaporation of liquid ammonia by hydrogenolysis of high boiling by-products of the hydrogenation when reactivated after deactivation of the catalyst, which allows the long-term use of the catalysts.
