Production of 6-amino-capronitrile and hexamethylene diamine from adiponitrile involves work-up by distillation with final recovery of adiponitrile

摘要

A process for the simultaneous production of 6-amino-capronitrile (ACN) and hexamethylenediamine (HDA) by hydrogenation of adiponitrile (ADN) in which, after separation of HDA by distillation, the ACN and ADN are separated in succession or simultaneously (in separate fractions) with a bottom temperature below 185 deg C. A process for the simultaneous production of ACN and HDA from ADN comprises (a) hydrogenation of ADN in presence of a catalyst based on a Subgroup VIII element to give a mixture containing ACN, HDA, ADN and high-boiling products, (b) separation of HDA from the mixture by distillation, (c1) separation of ACN by distillation and then (d1) separation of ADN by distillation or (c2) simultaneous separation of ACN and ADN in separate fractions. Distillation stage (d1) or (c2) is carried out with a bottom temperature below 185 deg C.