2026 Duisen Sulfuric Acid Leaching Kinetics of Zinc Waste

This work investigated the extraction behavior of Zn, Cu, and Fe during sulfuric acid leaching of metallurgical waste from the Ust-Kamenogorsk zinc production plant. At the same time, the detailed kinetic analysis was restricted to Zn dissolution. This study aimed to determine the structural and morphological characteristics of metallurgical wastes and the extraction efficiencies of Zn, Cu, and Fe, and to evaluate the apparent kinetics of Zn dissolution comparatively. The phase composition of the initial and mechanically treated samples was studied by X-ray diffraction analysis, functional groups by FTIR spectroscopy, and morphological features by scanning electron microscopy. Leaching experiments were conducted to assess the effect of sulfuric acid concentration, temperature, and process duration. The results showed that mechanical treatment produced qualitative morphological and structural changes in the slag and was accompanied by improved extraction of Zn, Cu, and Fe during sulfuric acid leaching. The extraction behavior depended on the experimental variable investigated. In the sulfuric acid concentration series, extraction from the mechanically treated sample reached 70.55± 0.88% for Zn, 90.50± 0.47% for Cu, and 42.37± 0.47% for Fe at 1.0 M H2SO4. In the leaching time series conducted at 1.0 M H2SO4 and 75 ◦C, Zn extraction reached 78.06± 0.92% at 120 min after mechanical treatment, whereas Cu extraction reached its maximum of 90.78± 0.55% at 60.