Process for the elution of fluorinated emulsifiers

US6436244B1 · kind B1 · utility

Assignee

• Dyneon GmbH · DE

Inventors

• Stephan Führer · Burgkirchen an der Alz, DE
• Gernot Lohr · Altötting, DE
• Werner Schwertfeger · Altötting, DE

Key dates

• Filing date: Jun 30, 2000
• Grant date: Aug 20, 2002
• Expiry date: Jun 30, 2020

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S203/90
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Fluorinated emulsifier acids bound to an anion exchanger resin can be eluted using a mixture of water, a compound of the formula M—X, in which M is an alkali metal or an alkylammonium ion, and X is hydroxyl, fluoride or chloride, and at least one organic solvent which completely dissolves the other components. For work-up of the eluent, this is advantageously subjected to steam distillation until all volatile constituents have been essentially removed, and the emulsifier acid is liberated from the steam distillation residue using a sufficiently strong acid. This emulsifier acid can advantageously be distilled off and collected as the ammonium salt in aqueous ammonia solution.