Method for recovering fluorinated emulsifiers from aqueous phases

US6706193B1 · kind B1 · utility

Assignee

• 3M INNOVATIVE PROPERTIES COMPANY · US

Inventors

• Georg Burkard · Tönning, DE
• Klaus Hintzer · Woodbury, US
• Gernot Lohr · Altötting, DE

Key dates

• Filing date: Dec 11, 2001
• Grant date: Mar 16, 2004
• Expiry date: Jan 16, 2022

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C51/47
• WIPO field: Environmental technology
• WIPO sector: Chemistry

Abstract

Fluorinated emulsifiers can be recovered from an aqueous phase containing small amounts of fluoropolymer particles by treating the aqueous phase with a small amount of a nonionic surface-active agent, bringing the aqueous phase adjusted in this way into contact with an anionic exchanger resin, and liberating the adsorbed emulsifier from the exchanger resin. The finely divided fluoropolymer can be precipitated quantitatively in the untreated aqueous phase or the eluate using flocculating agents.