Phenoxy-imine ligands for heavy metals extraction from Wastewater

Abstract

Natural occurrence and anthropogenic practices contribute to the release of pollutants, specifically heavy metals, in water over the years. Therefore, there is need for proper water treatment to minimize the harmful effects of the toxic heavy metals in water. A series of chelating ligands were used as model chelating agents for liquid-liquid extraction of copper(II), zinc(II), cadmium(II) and lead(II) cations from water using dichloromethane as the organic solvent. The relative affinities of these chelating ligands for copper(II), zinc(II), cadmium(II) and lead(II) by liquid-liquid extraction were found to be in the order copper(II)> zinc(II) > cadmium(II) > lead(II). The ligands showed binding efficiencies ranging from 75%-99% for copper(II), 72%-97% for zinc(II), 64%-87% for cadmium(II) and 51%-74% for lead(II). The extraction protocol was successfully applied to sewage effluent.