Catalyst for the prodcution of bis-para-aminocyclohexylmethane with few trans-trans-isomers by hydrogenation of methylenedianiline

摘要

The invention relates to catalysts for the preparation of bis-para-aminocyclohexylmethane by hydrogenation of methylenedianiline, ruthenium or rhodium being applied to a support in an amount of from 0.05 to 8% by weight, preferably 0.2 to 3% by weight in a layer thickness of from 5 to 150 mu m, preferably 10 to 80 mu m, which support comprises a calcined and superficially rehydrated transitional alumina, this alumina giving, in a suspension of 10 g in 300 ml of water at 25 DEG C after 60 min, at least an equilibrium pH of 8.2 and, after addition of 10 ml of 0.1 N hydrochloric acid to this suspension, at least a pH still of 6.0 after 30 minutes. Particularly suitable supports predominantly comprise hydrargillite or bayerite. To achieve the values required, the support can be furnished with an additional coating. The invention further describes a process for producing the catalyst and use therefore.