Recovery of adiponitrile from a mixture of adiponitrile, aminocapronitrile and hexamethylenediamine
US6599398B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 17, 2002 |
| Grant date | Jul 29, 2003 |
| Priority date | — |
| Expiry date | Jul 17, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S203/20
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Process for the recovery of a purified adiponitrile (ADN) from a mixture of adiponitrile, aminocapronitrile and hexamethylenediamine, utilizing two sequential distillations: (1) a first distillation in which the mixture is distilled in a distillation column at a head pressure that causes at least 7% of the ADN to go into the distillate, along with bishexamethylenetriamine (BHMT) and 2-cyanocyclopentylideneimine (CPI), and (2) a second distillation in which the distillate from the first distillation is distilled in a second distillation column at a head pressure sufficient to cause minimum-temperature azeotropy between ADN and BHMT, thereby allowing the majority of the BHMT and CPI to be removed from the second distillation as distillate, and ADN, substantially free of both BHMT and CPI, to be removed as bottoms.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.