Studies on the Separation of Cobalt and Nickel in Solution from Hydrometallurgical Processing of Ocean Cobalt-rich Crust

摘要

The leached solution obtained through treatment on ocean cobalt-rich crusts with activated sulfuric acid leaching processes was transformed into nickel and cobalt concentrated solution after removal of copper, zinc and manganese by extraction process. N235 was selected as the extractive solvent so as to separate cobalt from nickel in this solution. Influences of factors such as temperature, phase ratio and equilibrium time on effects of extraction were investigated, and optimum technique parameters determined as follows: temperature of 25 □ , phase ratio of 2～3:1, equilibrium time of 0.5 min. A four-stage counter-current mixing experiment was performed. It indicated that with a phase ratio (O/A) of 2.5:1 a rapid phase separation rate was assumed. Extraction ratio of cobalt was 99.99% and cobalt content remained in post-extraction solution was less than 0.005g/L, which indicated a complete separation of cobalt from nickel. This paved way for industrial application by providing experimental references.