Separation of nickel and cobalt from sulfate solutions by solvent extraction

The process for separating nickel and cobalt contained in aqueous sulfate solution which comprises treating said solution with an organic extractant for cobalt from the group consisting of organic phosphonic and phosphinic acids to provide a loaded organic solution containing the cobalt and a nickel raffinate having a nickel:cobalt ratio exceeding 10,000, stripping the cobalt loaded organic with aqueous sulfuric acid solution to regenerate said cobalt extractant and provide a cobalt strip solution containing cobalt and nickel as sulfate, treating said cobalt strip solution with an organic extractant for nickel essentially consisting of a non-chelating oxime with or without a compound from the group consisting of di(2-ethylhexyl) phosphoric acid and alpha-bromolauric acid to provide a cobalt raffinate having a cobalt:nickel ratio exceeding 10,000 and a loaded organic solution containing nickel, stripping said nickel-loaded organic with aqueous sulfuric acid solution to regenerate said nickel extractant and an aqueous sulfate solution containing nickel and cobalt which may be recycled to said cobalt extraction step to provide a solvent extraction process for separating nickel and cobalt in which no scrubbing operations are employed and in which cobalt recycle is minimized.