Method for replacement of phosgene synthesis column catalyst
US10046289B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 16, 2015 |
| Grant date | Aug 14, 2018 |
| Priority date | — |
| Expiry date | Jan 16, 2035 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01J2208/06
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
The present invention discloses a method of quickly desorbing phosgene from a catalyst in a phosgene synthesizing tower when the catalyst in the phosgene synthesizing tower is replaced. The method is carried out by first purging out easily-desorbed phosgene from the catalyst activated carbon in the phosgene synthesizing tower with nitrogen gas, then purging with ammonia gas, and the ammonia gas is reacted with the hardly-desorbed phosgene in the catalyst of the phosgene synthesizing tower. Then the phosgene synthesizing tower is rinsed with a water gun and then dried with hot gas. The phosgene content at an outlet of the phosgene synthesizing tower after purging is below 0.5 ppm, which can significantly save the time of the phosgene synthesizing tower for purging the phosgene, greatly reduce the amount of nitrogen gas consumed, and improve the safety of the process operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.