摘要 |
The invention relates to a method for hydrogenation of aromatic urethanes, which contain one or more aromatic rings and one or more urethane groups bonded directly and/or indirectly to one aromatic ring or to different aromatic rings, using hydrogen in the presence of a supported catalyst, which contains ruthenium as active metal. The catalyst support of the catalyst to be used according to the invention has a BET surface ranging from larger than 30 m<2>/g to smaller than 70 m<2>/g and more than 50% of the pore volume of the catalyst support is represented by macropores with a pore diameter of larger than 50 nm and less than 50% is represented by mesopores with a pore diameter of 2 to 50 nm. The method is suitable in particular for hydrogenation of dibutyl 4,4'-methylenedicarbanilate to dibutyl 4,4'-methylenedicyclohexylcarbamate with a trans-trans isomer content of <30%, preferably of <20%, particularly preferably of 5 to 15%.
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