Methods for improving solvent properties

Abstract

In hydrometallurgical processes, the separation of nickel and cobalt is challenging. Cyanex272 dialkyl phosphinic acid is generally used to separatet hese elements. The most effective separation requires that the reaction mixture be as pure as possible from various interferences such as carboxylic acids. This thesis investigates various possibilities for removing carboxylic acids from the extraction mixture. Possibility of utilizing different pH isotherms and different water solubilities of carboxylic acids and Cyanex 272 for separation was investigated. Normal phase chromatography was attempted with one minute fractioning and finally molecular catcher was tested. Separation of extractants in these experiments, with these parameters failed.Possibility of utilizing different pH isotherms and different water solubilities of carboxylic acids and Cyanex 272 for separation was investigated. Normal phasechromatographywasattemptedwithoneminutefractioningandfinally molecular catcher was tested. Separation of extractants in these experiments, with these parameters failed