Patent ID: 6231823
Filing Date: 2001-05-15
Classification: C22B,Y02P

Abstract:
In a process for separating cobalt values from nickel values, both as divalent ions, in an aqueous cobalt-containing, nickel sulphate solution in which the solution is contacted with a water-immiscible organic solution containing an acidic organic cationic extractant selective for cobalt over nickel in a cobalt extraction circuit so as to transfer the cobalt values from the aqueous solution to the organic solution, and separating the organic solution containing transferred cobalt values from an aqueous nickel-containing raffinate solution, the improvement comprising the additional steps of:(a) contacting at least a portion of the water-immiscible organic solution containing an acidic organic cationic extractant selective for cobalt over nickel with a nickel-containing ammoniacal solution to produce a nickel-loaded organic phase and a partially nickel-depleted raffinate; and(b) passing the nickel-loaded organic phase to the cobalt extraction circuit for selective cobalt extraction in which cobalt displaces nickel from the organic phase to produce a cobalt-depleted, nickel-enriched, raffinate, and a cobalt-loaded organic phase.