Separation of nickel and cobalt and manganese in solution

A process for the separation of individual metal values from a pregnant aqueous solution comprising a mixture of dissolved metal values and halide ions;

• the solution comprising, as a primary metal value, manganese and, as secondary metal value, cobalt;
• the process comprising:
• (1) contacting the pregnant aqueous solution with an organic water-immiscible ion exchange liquid extracting medium, the medium comprising an organic amine extracting agent selected from a group consisting of secondary, tertiary and quaternary organic amines, and selective to extract cobalt from the pregnant aqueous solution so as to form an organic amine extract containing the cobalt value and a portion of the manganese value and a cobalt-free aqueous raffinate substantially depleted in cobalt;
• (2) contacting the organic amine extract with a preliminary aqueous stripping solution containing dissolved halide ion in a concentration of at least about 0.5 Molar to strip from the amine extract a major proportion of the manganese value but only a minor proportion of the cobalt value so as to form an intermediate organic amine phase substantially reduced in manganese value and a preliminary aqueous strip solution of most of the manganese value;
• (3) contacting the intermediate organic amine phase with an aqueous acidic solution to form an acidic cobalt water strip solution containing the cobalt halide and the remaining manganese halide and an organic extracting medium substantially depleted in both cobalt value and manganese value;
• and (4) contacting the cobalt water strip solution with a manganese-extracting ion exchange liquid extracting medium, the medium comprising an organic manganese-extracting agent designed and adapted to selectively extract manganese from the cobalt water strip solution without substantially extracting cobalt, until the cobalt water strip solution is substantially depleted in manganese, thus forming a manganese-free aqueous solution containing the cobalt value and a manganese-containing organic extract solution.