Recovery of zinc and nickel from electrogalvanisation sludges using glycine solutions

• Published in: Electrochimica acta Vol. 46; no. 2; pp. 279 - 287
• Main Authors: Rodriguez-Torres, I, Valentin, G, Chanel, S, Lapicque, F
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.11.2000; Elsevier
• Subjects: Applied sciences; Exact sciences and technology; Glycine; Leaching; Other industrial wastes. Sewage sludge; Pollution; Solid wastes; Speciation diagrams; Wastes; Zincnickel deposition; Speciation diagrams; Glycine; Leaching; Zincnickel deposition; Solid wastes; Nickel base alloys; Zinc base alloys; α-Aminoacid; Waste recovery; Electrochemical treatment; Waste treatment; Solid waste; Alkaline leaching; Solvent extraction
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/S0013-4686(00)00583-1

The paper deals with a novel technique for metal recovery from electrogalvanisation sludges using glycine. Zinc and nickel contained in these sludges can be recovered by leaching with glycine and upon addition of sodium hydroxide: high efficiency and selectitivity were obtained from other metal species e.g. iron or calcium. ZnNi alloy deposition was investigated with both synthetic media and solutions prepared by leaching samples of industrial sludges at pH 8. The electrolytic treatment of the solutions prepared was carried out in a batch reactor operated in recycle mode. Zinc was found to deposit with current efficiencies of approx. 50%, hydrogen evolution competing with the deposition. More than 90% of the zinc contained was recovered at the cathode. Besides, nickel deposition appeared to be inhibited by glycine and the efficiency of the overall technique was quite poorer for nickel than for zinc.