Methods for purifying and recovering contaminated refrigerants with aqueous solutions of bases
US5698750A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 30, 1995 |
| Grant date | Dec 16, 1997 |
| Priority date | — |
| Expiry date | Oct 30, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C17/395
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Refrigerants, such as Freon.RTM. 12 and other potential ozone depleting substances will be in short supply as their production is phased out, and until existing refrigeration equipment is retrofitted to receive more environmentally friendly refrigerants. Existing supplies of such refrigerants when contaminated with other refrigerants especially hydrofluoroalkanes like Freon 22 can form azeotropes, which are not readily separated by conventional distillation methods, are selectively decomposed in-situ by reacting with aqueous solutions of metal hydroxides or other bases. The remaining non-reacted refrigerant-containing composition is readily recycled by separation and recovery methods from the reaction mixture to provide a reusable refrigerant composition virtually free of contaminating refrigerant.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.