Extraction of cobalt from cobalt slag from electrowinning nickel solution

existElectrodeposited NickelDuring the process, the nickel and cobalt in the anode are electrochemically dissolved into the solution. When the anolyte is purified and the impurities are removed, the cobalt in the solution is deposited in the cobalt slag in the form of Co(OH)3. The cobalt slag contains 6 Cobalt from 7 percent to 7 percent can be used to produce cobalt oxide or cobalt metal. The process includes cobalt slag dissolution, leachate purification to remove impurities, nickel and cobalt separation, and cobalt oxide (or metal cobalt) preparation.

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At 65-75 degrees Celsius, add Na2SO3 to sulfuric acid solution to reduce Co3 to CO2 and dissolve:

2Co (OH) 3 Add Na2SO3 Add 2H2SO4 === 2CoSO4 Add Na2SO4 Add 5H2O When dissolved at 95 degrees Celsius, add NaClO3 to remove Fe2 Add oxidative hydrolysis deposition. After putting the iron solution into the extraction tank, use P204 extractant to remove copper and remaining iron After copper removal, the solution was separated from nickel and cobalt with P507. Cobalt-containing organic phase was back-extracted with the solution to obtain a COCl2 solution of Co75g\/L. This solution can be used to produce nickel in insoluble anode cells. Cobalt can also be deposited with oxalic acid , and then calcined to form cobalt oxide powder. The electrolysis process conditions are: current density 400A\/m2, cell voltage 3-4v, electrolysis temperature 60 degrees Celsius, and current efficiency 94 percent.