Method for purifying fluorinated compound
US8444857B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 9, 2010 |
| Grant date | May 21, 2013 |
| Priority date | — |
| Expiry date | May 18, 2031 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F14/18
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A method for purifying a fluorinated carboxylic acid having an etheric oxygen atom and its derivative, with small decomposition and inclusion of impurities. A liquid containing at least one member selected from the group consisting of a fluorinated compound represented by application formulae (1) and (2) is held at a heating temperature of at most 150° C. and distilled. Further, the liquid is a liquid obtained from any of a waste liquid after an aqueous emulsion of a fluoropolymer is coagulated and the fluoropolymer is separated, an aqueous liquid obtained by cleaning an exhaust gas in a step of drying and/or a step of heat treatment of the separated fluoropolymer, and a liquid obtained by cleaning an anion exchange resin which has been brought into contact with the waste liquid or an aqueous dispersion obtained from the aqueous emulsion of the fluoropolymer, with an alkaline aqueous solution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.