Abstract: A low viscosity water insoluble extraction reagent composition according to the invention is comprised of: (a) an extractant selected from the group consisting of an aldoxime, a ketoxime, or a combination thereof; (b) an equilibrium modifier having a Brookfield viscosity of equal to or less than about 5 centapoise at 25° C. and a flash point equal to or greater than about 141° F. wherein the molar ratio of modifier to extractant is from about 0.05 to about 2.0 so as to provide a net copper transfer greater than that achieved in the absence of modifier. Such low viscosity extractants afford higher recoveries of copper, permit reduced equipment size such as smaller mixers and settlers and the use of reduced amounts of less overall organic inventory.

Abstract: A low viscosity water insoluble extraction reagent composition according to the invention is comprised of: (a) an extractant selected from the group consisting of an aldoxime, a ketoxime, or a combination thereof; (b) an equilibrium modifier having a Brookfield viscosity of equal to or less than about 5 centapoise at 25° C. and a flash point equal to or greater than about 141° F. wherein the molar ratio of modifier to extractant is from about 0.05 to about 2.0 so as to provide a net copper transfer greater than that achieved in the absence of modifier. Such low viscosity extractants afford higher recoveries of copper, permit reduced equipment size such as smaller mixers and settlers and the use of reduced amounts of less overall organic inventory.