Keywords
selective leaching
sulfuric acid leaching
metal sulfates
water leaching
non-ferrous metals
hydrometallurgy
extraction efficiency
How to Cite
Abstract
In this study, the possibilities of efficiently separating iron, zinc, and copper from copper smelting slag, which is a waste of the copper industry, using a non-conventional hydrometallurgical method were investigated. The recycling of such wastes is important not only for the recovery of valuable metals but also for reducing their negative impact on the environment. In order to eliminate technological problems that arise during the filtration stage after sulfuric acid leaching of copper smelting slag, the research was carried out in three stages. First, the slag sample was selectively leached with sulfuric acid; in the second stage, the obtained solution was dried; and in the final stage, the resulting solid metal sulfates were selectively leached with water. During the sulfuric acid leaching process, the effects of acid concentration, leaching time, temperature, and stirring speed on the transfer of metals into the solution were comprehensively investigated. The experimental results showed that an acid concentration of 2 M, a leaching time of 120 minutes, a temperature of 90 °C, and a stirring speed of 300 rpm are optimal conditions for metal dissolution. Under these conditions, the degree of metal dissolution into the solution was 89.5% for Cu, 88.7% for Zn, and 59.2% for Fe. The solution obtained after selective leaching was dried at 150 °C for 90 minutes to obtain solid metal sulfates. In the next stage, this product was selectively leached with water, and it was determined that a leaching time of 40 minutes and a temperature of 40 °C are the most favorable conditions for the transfer of metals into the solution.
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Copyright (c) 2026 Axmedov, M.S., Yuldoshev, S.M., Azimova, A.B. (Muallif)