Adsorbent for purifying perfluorocarbon, process for producing same, high purity octafluoropropane and octafluorocyclobutane, and use thereof
US7094935B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 14, 2001 |
| Grant date | Aug 22, 2006 |
| Priority date | — |
| Expiry date | Nov 18, 2022 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B32/336
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
To provide a purification adsorbent capable of effectively removing impurities contained in a perfluorocarbon and obtaining a perfluorocarbon reduced in the impurity content to 1 ppm by mass or less; a process for producing the adsorbent; high-purity octafluoropropane or octafluorocyclobutane; processes for purifying and for producing the octafluoropropane or octafluorocyclobutane; and uses thereof. Purification is performed using a purification adsorbent produced by a method comprising (1) washing an original coal with an acid and then with water, (2) deoxidizing and/or dehydrating the original coal, (3) re-carbonizing the original coal at a temperature of from 500 to 700° C. and (4) activating the original coal at a temperature of from 700 to 900° C. in a mixed gas stream containing an inert gas, carbon dioxide and water vapor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.