Polymers for metal extractions in carbon dioxide

US6176895A · kind A · utility

Inventors

• Joseph M. DeSimone · Monte Sereno, US
• William Tumas · Los Alamos, US
• Kimberly R. Powell · Chapel Hill, US
• T. Mark McCleskey · Los Alamos, US
• Timothy J. Romack · Durham, US
• James B. McClain · Raleigh, US
• Eva R. Birnbaum · Los Alamos, US

Key dates

• Filing date: Nov 4, 1998
• Grant date: Jan 23, 2001
• Expiry date: Nov 4, 2018

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P10/20
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A composition useful for the extraction of metals and metalloids comprises (a) carbon dioxide fluid (preferably liquid or supercritical carbon dioxide); and (b) a polymer in the carbon dioxide, the polymer having bound thereto a ligand that binds the metal or metalloid; with the ligand bound to the polymer at a plurality of locations along the chain length thereof (i.e., a plurality of ligands are bound at a plurality of locations along the chain length of the polymer). The polymer is preferably a copolymer, and the polymer is preferably a fluoropolymer such as a fluoroacrylate polymer. The extraction method comprises the steps of contacting a first composition containing a metal or metalloid to be extracted with a second composition, the second composition being as described above; and then extracting the metal or metalloid from the first composition into the second composition.