Method for making high flux, high salt rejection cellulose desalting membranes

US8123945B2 · kind B2 · utility

Assignees

• The United States of America as represented by the Secretary of the Interior, The Bereau of Reclamation · US
• Separation Systems Technology · US

Inventors

• Andrew Murphy · Littleton, US
• Saied Delagah · Denver, US
• Robert L. Riley · Vista, US

Key dates

• Filing date: May 9, 2007
• Grant date: Feb 28, 2012
• Expiry date: Sep 5, 2029

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01D2325/24
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

A method is provided for producing a high flux, high salt rejection cellulose acetate desalination membrane. In this method, cellulose acetate polymer is dissolved in a first solvent such as methylene chloride or 2-methyltetrahydrofuran to produce a solution. Further steps involve stirring the solution, and thereafter permitting the solution to settle, for a time sufficient for a majority of the cellulose acetate to precipitate out of the solution to form a cellulose acetate precipitate. Next, the cellulose acetate precipitate is stirred into an excess methanol. Thereafter, the cellulose acetate is filtered out and used in making the desalination membrane.