Regeneration of zeolites used for purifying 1,1,1,2-tetrafluoroethane
US5087778A · kind A · utility
17Cited by
3References
20Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Apr 10, 1990 |
| Grant date | Feb 11, 1992 |
| Priority date | — |
| Expiry date | Apr 10, 2010 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01J20/3491
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
1,1,1,2-Tetrafluoroethane (R134a) is purified to remove 50-10,000 wt. ppm of 2-chloro-1,1-difluoroethylene (R1122) by contacting with a zeolite or carbon molecular sieve having an average pore diameter of 3.8 to 4.8 Angstroms. The zeolite or carbon molecular sieve is regenerated by inert gas stripping residual R134a, followed by a regeneration at elevated temperatures using an inert gas. Regeneration of the zeolite or carbon molecular sieve is accomplished without the substantial reduction in capacity for impurities.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.