Continuous process for the gaseous-phase preparation of trichlorotrifluoroethane, dichlorotetrafluoroethane and monochloropentafluoroethane in controlled proportions
US4605798A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 25, 1981 |
| Grant date | Aug 12, 1986 |
| Priority date | — |
| Expiry date | Nov 25, 2001 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C17/21
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
This invention relates to a continuous gaseous-phase process for the preparation of trichlorotrifluoroethane, dichlorotetrafluoroethane and monochloropentafluoroethane, in predetermined proportions, from tetrachloroethylene, chlorine and hydrofluoric acid in the presence of a catalyst. The process is characterized by the combination of two chlorination-fluorination reactors in sequence, a parallel fluorination-dismutation reactor, and a separation unit for extracting the desired products and recycling recovered hydrofluoric acid and non-fluorinated or insufficiently fluorinated products. The process advantageously yields dichlorotetrafluoroethane containing less than 7% asymmetric isomer, and trichlorotrifluoroethane containing less than 2% asymmetric isomer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.