The Effect of Various Parameters in the Sulfuric Acid Leaching of Low Grade Zinc Oxide Ore of Niğde-Türkiye

The aim of this study was to investigate the main parameters affecting the leaching of low grade zinc oxide ores with sulfuric acid. The influence of leaching time (5 to 480 minutes), sulfuric acid concentration (25 to 125 g/L), leaching temperature (25 to 90 °C), particle size (-104 µm, -82 µm, -60 µm, -49 µm) and solid/liquid ratio (1/10, 1/7.5, 1/5, 1/4) was investigated. The effects of these process parameters were studied with to achieve maximum zinc extraction with minimum iron extraction and acid consumption. The optimum parameters for sulfuric acid leaching of zinc ore were determined to be 60 min leaching time, 75 g/L sulfuric acid concentration, 80 oC leaching temperature, 1/10 solid/liquid ratio and -60 µm particle size. Under these optimum conditions, Zn extraction (%), Fe extraction (%) and acid consumption (ton H2SO4/ dissolved ton Zn) were obtained 88.68%, 25.83% and 5.47 ton H2SO4/ dissolved ton Zn respectively.