Process for the preparation of aldehydes

摘要

Process for the preparation of aldehydes by the hydroformylation of olefins having more than seven carbon atoms, comprising the step of hydroformylation by means of a rhodium catalyst dissolved in homogeneous reaction medium, the separation of the rhodium catalyst from the material discharged from the hydroformylation reaction, and the recycling of the rhodium separated off from the material discharged from the hydroformylation in the hydroformylation step by extracting the rhodium catalyst from the material discharged from the hydroformylation by means of an aqueous solution of a nitrogen-containing complexing agent from the group consisting of pyridines, quinolines, 2,2'-bipyridines, 1,10-phenanthrolines, 2,2'-biquinolines, 2,2',6',2''-terpyridines and porphines which are optionally substituted, sulphonated or carry sulphonated substituents and/or from the group consisting of carboxylated pyridines, carboxylated quinolines, and 2,2'-bipyridines, 1,10-phenanthrolines, 2,2'-biquinolines, 2,2',6',2''-terpyridines and porphines which are optionally substituted, carboxylated or carry carboxylated substituents, in the aqueous phase and feeding back the aqueous, rhodium-containing extract to the hydroformylation step.