An Efficient Approach to Chlorine Removal in the Zinc Hydrometallurgical Process

Najafi, Matin; Behnajady, Bahram; Karimi, Saeid

doi:10.22111/jesm.2025.52011.1026

An Efficient Approach to Chlorine Removal in the Zinc Hydrometallurgical Process

Document Type : Original Research Paper

Authors

¹ Faculty of Materials Engineering, Sahand University of Technology, Sahand New Town, Tabriz, Iran.

² Department of Metallurgy and Materials Engineering, Hamedan University of Technology, Hamedan, Iran

10.22111/jesm.2025.52011.1026

Abstract

Nowadays, most of the metallic zinc is produced through hydrometallurgical processes. To attain high-purity zinc through electrowinning, the concentration of chlorine ions in the electrolyte should not exceed 0.5 g/L due to its negative consequences. One in particular is the corrosion of non-consumable lead anodes, which is responsible for the dissolution of Pb that causes impurity in the produced zinc metal. Moreover, chlorine emission in the work environment could be a danger to the health of staff, which stems from the oxidation of chlorine ions on the non-consumable Pb anodes. In this research, a potential alternative procedure is employed to significantly reduce chlorine in zinc concentrate. The results showed that under the appropriate conditions of T=60 °C and 1 h of experiment, two-step dichlorination using water along with 20 g/L Na2CO3 had a salient efficiency of 98% and the lowest amount of 0.48 g/L chlorine remaining in the leaching solution. Compared to traditional dichlorination methods of zinc, the employed procedure had satisfying dichlorination efficiency, considering the economic aspects of the produced zinc, particularly on the industrial scale.

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