Selective Recovery of Copper, Cobalt, and Nickel from Aqueous Chloride Media using Solvent Impregnated Resins

Abstract

Selective recovery of copper, cobalt, and nickel from acidic chloride media was investigated with solvent impregnated resins (SIRs) containing acidic organophosphorus extractants. The adsorption of each metal with the SIR proceeds via a cation exchange mechanism. An SIR containing 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (PC-88A) has high selectivity for Cu²⁺, and the order of selectivity is Cu²⁺ > Co²⁺ > Ni²⁺. Effective adsorption-elution can be achieved by chromatographic operation for the selective recovery of Cu²⁺ from a ternary metal solution. High selectivity for Co²⁺ was observed using a SIR comprising bis-2,4,4-trimethylpentylphosphinic acid (Cyanex 272) and can be effectively separated from a Co and Ni binary metal solution by column adsorption. A simple and effective process flow sheet is proposed for selective recovery of Cu²⁺, Co²⁺, and Ni²⁺ from aqueous chloride media using the two SIRs.

Keywords:

• Adsorption
• recovery
• copper
• cobalt
• nickel
• solvent impregnated resins

ACKNOWLEDGMENTS

We are grateful for the financial support through a Grant-in-Aid for Scientific Research (No. K2127 and K22091) from the Ministry of Environment of Japan.