Method of recovering fluorinated acid surfactants from adsorbent particles loaded therewith

US7754914B2 · kind B2 · utility

Assignee

• 3M INNOVATIVE PROPERTIES COMPANY · US

Inventors

• Stephan Führer · Burgkirchen an der Alz, DE
• Klaus Hintzer · Woodbury, US
• Gernot Lohr · Altötting, DE
• Egon Obermaier · Taubenbach, DE
• Werner Schwertfeger · Altötting, DE

Key dates

• Filing date: Jan 14, 2005
• Grant date: Jul 13, 2010
• Expiry date: Aug 5, 2027

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C51/493
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The present invention provides a method of recovering a fluorinated acid surfactant or salt thereof from adsorbent particles to which said fluorinated acid surfactant has been adsorbed. The method comprises mixing adsorbent particles having adsorbed fluorinated acid surfactant or salt thereof with an alcohol and optionally an acid. The mixture is generally heated to cause esterification of the fluorinated acid surfactant or salt thereof with the alcohol so as to form an ester derivative of the fluorinated acid surfactant, distilling the mixture to form a distillate comprising the ester derivative, separating the ester derivative from the distillate and optionally feeding the remainder of the distillate back into the mixture.