Process for the preparation of a high-purity cobalt intermediate

摘要

A process for the preparation and purification of a cobalt intermediate from a cobalt sulphate solution containing cationic and anionic impurities, including the successive steps of: (i) reacting the cobalt sulphate solution with an organic reagent to extract unwanted cationic impurities from the sulphate solution; (ii) extracting the cobalt from the sulphate solution with an organic reagent, to create a cobalt loaded organic phase substantially free of all anionic impurities; (iii) stripping the cobalt loaded organic phase with a high strength ammoniacal ammonium carbonate solution, to create an ammoniacal ammonium carbonate strip liquor rich in cobalt II ammines; (iv) converting the cobalt II ammines to cobalt III tetrammines; (v) extracting the majority of nickel from the cobalt rich ammoniacal liquor with a suitable organic reagent; and (vi) recovering the cobalt from the cobalt rich ammoniacal liquor.