Zirconium tri-ethylene tetra-amine ligand-chelator complex based cross-linked membrane for selective recovery of Cu2+ by electrodialysis

Cross-linked zirconium tri-ethylene tetra-amine (ZrT) chelating membranes were prepared by sol–gel method in aqueous media for selective removal of Cu2+ in presence of other bi-valent metal ions. Adsorption studies confirmed very high Cu2+ uptake in compare to other bi-valent metal ions (Ni2+, Zn2+, and Mn2+). UV-DRS spectra confirmed d–d transition band of Cu2+, centered in a pseudo-octahedral environment. Developed ZrT membrane exhibited good thermal, mechanical, and chemical stabilities. Furthermore, conductivity and counter-ion transport studies of these membranes suggested their potential application for separating Cu2+ by electrodialysis. Electro-dialytic studies revealed very high Cu2+ flux across ZrT membranes in comparison with other bi-valent metal cations (Ni2+, Zn2+, and Mn2+). Selective recovery of Cu2+ in the membrane phase was attributed to its structural morphologies. Furthermore, high separation factor for separating Cu2+/Ni2+, Cu2+/Zn2+, and Cu2+/Mn2+, suggested practical applications of ZrT chelating membranes for recovery Cu2+ from industrial waste water.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (250 K)Download as PowerPoint slideHighlights► Cross-linked zirconium tri-ethylene tetra-amine (ZrT) chelating membranes. ► Selective separation/removal of Cu2+ from other bi-valent metal ions. ► Electro-dialytic separation Cu2+ from other bi-valent metal cations. ► Pseudo-octahedral environment centered d–d transition band of Cu2+.