Liquid-liquid extraction of copper(II), zinc(II), cadmium(II), and lead(II) from aqueous solution and sewage effluent using phenoxy-amino ligands

Abstract

The phenoxy-amino ligands 2-(((2-(diethylamino)ethyl)amino)methyl)phenol (L1) and 2-(((2-mercaptoethyl)amino)methyl)-phenol (L2) were studied as model chelating agents for liquid-liquid extraction of copper(II), zinc(II), cadmium(II), and lead(II) cations from water using dichloromethane-water biphasic system. The relative affinities of these chelating ligands for copper(II), zinc(II), cadmium(II), and lead(II) by liquidliquid extraction were found to be in the order copper(II) > zinc(II) > cadmium(II) > lead(II). The ligands L1 and L2 showed binding efficiencies ranging from 78%-97% for copper(II), 75%-91% for zinc(II), 76%-92% for cadmium(II), and 59%-67% for lead(II). The extraction protocol was successfully applied to sewage effluent.