Alkaline leaching of zinc from low-grade oxide zinc ore using ammonium citrate as complexing agent

Abstract

In this study, the effect of ammonium citrate (AC) on the leaching of low grade zinc oxide ore in the 5 m ammonia solution was studied. AC served as a leaching agent and complexing agent, respectively. The results of the leaching experiments showed that AC increased the leaching rate of zinc, which increased with the rise of the concentration of AC. Under conditions of temperature of 30°C, reaction time of 60 min, citric acid concentration of 1 mol/l and solid to liquid ratio of 1:5, 88.83% of zinc was leached. The enhancement mechanism of AC to the leaching rate of zinc was studied by Fourier transform infrared (FT-IR) spectra.