Methods for purifying and recovering contaminated refrigerants with solutions of bases in organic solvents
US5616821A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 30, 1995 |
| Grant date | Apr 1, 1997 |
| Priority date | — |
| Expiry date | Jan 30, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K5/044
- 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 chlorofluorohydrocarbons like Freon 22 form azeotropes, which are not readily separated by conventional distillation methods, are selectively decomposed in-situ by reacting with bases such as metal hydroxides in aqueous solutions or compatible organic solvents. 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 practically free of contaminating refrigerant.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.