Phosgenation method
US5693853A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 14, 1995 |
| Grant date | Dec 2, 1997 |
| Priority date | — |
| Expiry date | Nov 14, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C263/10
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A method of phosgenation while using carbonyl chloride produced from chlorine and contaminated carbon monoxide. The obtained contaminated carbonyl chloride is purified prior to being delivered to the phosgenation process. The carbonyl chloride is purified by absorption in a solvent and the obtained carbonyl chloride solution is used for the phosgenation reaction. The carbonyl chloride is conveniently purified in an absorption column which is also used to recover carbonyl chloride from waste gases deriving from the phosgenation process, wherein the solution of fresh and recovered carbonyl chloride is delivered commonly to the phosgenation process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.