Zinc Recovery from Electric Arc Furnace Dust via Selective Leaching with Ammonium Chloride Solution

Abstract

Electric arc furnace dust (EAFD) generated during steel manufacturing contains significant quantities of valuable metals, particularly zinc, along with hazardous constituents that pose environmental and disposal challenges. This study investigates the recovery of zinc from EAFD through selective leaching using ammonium chloride solution as an environmentally favorable hydrometallurgical approach. The process focuses on maximizing zinc extraction efficiency while minimizing the dissolution of unwanted impurities such as iron and other metallic components. Experimental analyses were conducted under varying operational conditions, including leaching temperature, ammonium chloride concentration, reaction time, liquid-to-solid ratio, and agitation speed, to evaluate their influence on zinc recovery performance. The leaching mechanism and reaction kinetics were examined to understand the dissolution behavior of zinc-bearing phases present in the furnace dust. Results demonstrated that selective leaching with ammonium chloride effectively enhances zinc solubility and achieves high recovery efficiency with improved selectivity compared to conventional acidic leaching processes. The optimized process conditions significantly reduced secondary waste generation and promoted efficient separation of zinc from complex industrial residues. Kinetic modeling confirmed that the leaching process is governed by diffusion and surface chemical reactions under controlled operating parameters. The proposed recovery technique offers a sustainable and economically viable solution for resource recovery and waste valorization in metallurgical industries.