Process for the separation of hydrogen fluoride from its mixtures with 1,1,1-trifluoro-2-chloroethane
US5426254A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 10, 1993 |
| Grant date | Jun 20, 1995 |
| Priority date | — |
| Expiry date | Sep 10, 2013 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B7/196
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The invention relates to the separation of hydrogen fluoride (HF) from its mixtures with 1,1,1-trifluoro-2-chloroethane (F133a). By settling of the mixture of HF and F133a in the presence of trichloroethylene at a temperature below 0.degree. C., a lower organic phase which is poor in HF and an upper phase which is rich in HF are obtained. The latter can be directly recycled to the fluorination reactor or subjected to a distillation in order to separate, at the head, the HF/F133a azeotrope which is returned to the settler, and to recover, at the foot, practically pure HF. By distillation of the lower phase, the HF/F133a azeotrope which is returned to the settler is separated at the head and a mixture of F133a and trichloroethylene is recovered at the foot. The latter mixture is subjected to a distillation which makes it possible to separate, at the head, pure F133a from trichloroethylene at the foot.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.