Patent · US Active

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

US7312362B2 · kind B2 · utility

12Cited by

7References

5Claims

0Family size

Assignee

Bayer MaterialScience AG · DE

Inventors

Berthold Keggenhoff · Krefeld, DE
Richard Adamson · Leichlingen, DE
Rudolf Uchdorf · Shanghai, CN
Fritz Pohl · Wittmund, DE

Key dates

Filing date	Jan 24, 2007
Grant date	Dec 25, 2007
Priority date	—
Expiry date	Jan 24, 2027

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC07C263/10
WIPO fieldOrganic fine chemistry
WIPO sectorChemistry

Abstract

The present invention relates to a process for the production of mixtures of di- and polyamines of the diphenylmethane series (MDA) containing less than 1,000 ppm of water and less than 200 ppm of aniline by reaction of aniline and formaldehyde in the presence of acid catalysts and subsequent separation of the acid catalyst and subsequent distillative separation of water and aniline in an at least a two-stage distillation including a flash evaporation and subsequent cooling.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.