Solvent extraction of cobalt (II) from sulfate solutions with cobalt extractants

摘要

Nickel and cobalt contained in aqueous sulfate solution are separately recovered by counter-current solvent extraction using a cobalt-selective organic extractant while scaling of equipment and cobalt recycle are minimized by controlling aqueous pH at the extraction, scrubbing and stripping stages to maximize cobalt loading and selectivity of the extractant while loading scale-causing ions such as calcium and magnesium in the extractant and removing them from the circuit with the aqueous cobalt strip solution.