ELECTRO-ASSISTED SOLVENT-EXTRACTION OF CU2+, NI2+ AND CD2+

A novel separation method, i.e. electro-assisted solvent extraction, b ased on the principles of two-phase electrochemistry, has been demonst rated for the successful separation of Ni2+, Cu2+ and Cd2+ ions. 2-Hep tanone has been used as the organic solvent for the transfer of Ni2+, Cu2+ and Cd2+ facilitated by 2,2';6',2 ''-terpyridine. It is shown tha t extraction efficiency depends on the concentration ratio of ligand t o metal ion and importantly, on the applied interfacial potential diff erence. Tt was Found that Ni2+ (not Cd2+ or Cu2+) extraction is suppre ssed in the presence of Mg2+ ion due to competitive complexation. (C) 1998 Elsevier Science Ltd. All rights reserved.