Process for the preparation of di- and polyamines of the diphenylmethane series

• Main Authors: Wershofen, Stefan, Pirkl, Georg, Adamson, Richard
• Format: Patent
• Language: English
• Published: 01.09.2020
• Subjects: ACYCLIC OR CARBOCYCLIC COMPOUNDS; CHEMISTRY; METALLURGY; ORGANIC CHEMISTRY

The invention relates to a process for the preparation of di- and polyamines (MDA) of the diphenyl methane series. Firstly crude MDA is prepared and is then subjected to a distillation process, wherein the distillation process comprises the following steps: in a distillation column, separating off a stream containing aniline and water as a head product so as to obtain the first product stream as asump product; in said distillation column or in an apparatus arranged downstream of the distillation column, performing stripping with steam so as to obtain a gaseous stream containing aniline, waterand MMDA; partially condensing the gaseous stream containing aniline, water and MMDA so as to obtain a liquid stream containing MMDA and water (and optionally aniline) and a gaseous stream containinganiline, water (and optionally MMDA); drying the liquid stream containing MMDA and water (and optionally aniline) obtained by partial condensation so as to obtain the second product stream.