Process for drying CH.sub.2 F.sub.2 refrigerant utilizing zeolite
US6020281A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 20, 1997 |
| Grant date | Feb 1, 2000 |
| Priority date | — |
| Expiry date | Jun 20, 2017 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF25B43/003
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Difluoromethane (R-32) is of current interest as a partial replacement for chlorodifluoromethane (R-22) refrigerant heretofore widely used in vapor compression refrigeration systems. R-32 has, however, proved to be more reactive than is desirable with the zeolite A adsorbent-desiccant compositions used in such systems to prevent corrosion and freeze-up problems. The potassium cation form of a zeolite A molecular sieve--with at least 60 per cent of the sodium cations replaced with potassium ions, agglomerated with a clay binder and pore-reduced to essentially exclude the adsorption of R-32, and having essentially no reactivity with difluoromethane--has been found to be an effective desiccant for refrigerants comprising difluoromethane.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.