Method of making a multilayer capillary membrane

US5242636A · kind A · utility

Assignee

• Akzo N.V. · NL

Inventors

• Heinz-Dieter Sluma · Großostheim, DE
• Robert Weizenhofer · Zell am Harmersbach, DE
• Alfons Leeb · Kleinwallstadt, DE
• Karl Bauer · Schattendorf, AT

Key dates

• Filing date: Nov 27, 1991
• Grant date: Sep 7, 1993
• Expiry date: Nov 27, 2011

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01D69/1212
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

A multilayer membrane for separating gas mixtures includes a polymer supporting membrane with a voids volume of more than 50% and a coating of two or more separating layers made of two or more different polymers. A hollow capillary serving as the supporting membrane is guided through the central bore of a spinneret. The spinneret has one or several concentric annular slits and/or annular grooves, through each of which a solution of one of the polymers forming the separating layers is applied to the supporting membrane. The spinneret terminates in a sealed chamber in which the solvent or solvents of the polymer solutions is/are evaporated and removed. The coated supporting membrane is drawn out of the chamber and wound up, possibly following aftertreatment with heat and/or liquids.