Leaching of Cu, Zn, and Pb from Sulfidic Tailings Under the Use of Sulfuric Acid and Chloride Solutions

Abstract The imbalance between raw materials of high economic importance and their supply has increased the search for new approaches to obtain valuable elements from mining tailings. In this study, extraction copper, zinc, lead sulfidic tailing in sulfate–chloride media was investigated. A 3 Box–Behnken design applied evaluate three variables over a 4-h testing period: sulfuric acid concentration (0.01–1.0 mol/L H 2 SO 4 ), sodium chloride (10–60 g/L NaCl), temperature (20–70 °C). showed two optimum working regions: combination NaCl level, low medium level leaching, while copper medium–high level. had only slight impact on leaching. Based these results, two-stage leaching performed. first stage carried out under an experimental condition that favored (60 NaCl, 0.01 , 45 °C, 1 h, 10:1 liquid-to-solid ratio), whereas second maximized zinc 0.5 70 24 ratio). global rate 66.8 ± 3.0% 84.1 5.2% 93.9 3.2% lead. iron arsenic content were also leached by about 20 50% at end stage. study demonstrated use considerably improved desired metals was, therefore, suitable recovery. Graphical