Distillative method for separating hexamethylenediamine from a mixture comprising hexamethylenediamine, 6-aminocapronitrile and tetrahydroazepine
US6887352B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 7, 2003 |
| Grant date | May 3, 2005 |
| Priority date | — |
| Expiry date | Mar 7, 2023 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C209/84
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A method for recovering hexamethylene diamine (HMD) from a mixture comprising HMD, 6-aminocapronitrile (ACN) tetrahydroazepine (THA), and adiponitrile (ADN) is disclosed.The method includes introducing the mixture into a first distillation column, separating as a group the HMD, ACN and at least a portion of the THA as distillate from the ADN. The first distillation column is operated at a temperature and pressure to minimize isomerization of the ADN into 2-cyanocyclopentylideneimine(CPI). The distillate of the first distillation column is introduced into a subsequent distillation column and the HMD is separated from the ACN and THA.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.