Abstract: A process for the separation of unwanted ferric, iron and zinc impurities from a cobalt sulphate solution containing these impurities, the process including the steps of (i) reacting the cobalt sulphate solution with an organic reagent specific for the removal of iron and zinc at an initial pH of less 2.8 to remove the majority of the unwanted ferric iron impurities; and (ii) slowly raising the pH of the solution to about 3.5 in order to remove zinc impurities and any remaining ferric iron impurities.

Abstract: A process for the preparation and purification of a cobalt oxide hydroxide intermediate from a cobalt sulphate solution containing cationic and anionic impurities, including the successive steps of (i) contacting the cobalt sulphate solution with an organic reagent to extract iron and zinc cationic impurities from the sulphate solution; (ii) extracting the cobalt from the sulphate solution with an organic reagent to produce a cobalt loaded organic phase substantially free of all anionic impurities; (iii) stripping the cobalt loaded organic phase with a concentrated ammoniacal ammonium carbonate solution to produce an ammoniacal ammonium carbonate strip liquor rich in cobalt II ammines; (iv) oxidizing the cobalt II ammines in the ammoniacal ammonium carbonate strip liquor to cobalt III tetraammines; (v) extracting the majority of nickel impurity from the cobalt III tetraammine rich ammoniacal liquor with an organic reagent; and (vi) recovering the cobalt from the cobalt III tetraammine rich ammoniacal liquor.