Abstract
With excessive consumption of sulfide ores, using low-grade Pb-Zn mixed ores to obtain Zn has attracted more attention. Acid leaching is an effective method for Zn recovery; however, a high concentration of inorganic acid brings severe environmental issues, including acidic wastewater, contaminated soil, etc. Compared with inorganic acid, organic acid showed lower acidity and toxicity. Herein, we applied an effective method for Zn recovery from carbonate-type Pb-Zn mixed ore (CMO), by combining organic acid leaching with mechanical activation. Among the organic acids applied (lactic, malonic, citric, amber, acetic, and tartaric one), lactic acid was selected for its high leaching efficiency. The optimum condition was identified via response surface methodology, with a lactic acid concentration of 1.15 mol/L, L/S ratio of 20, leaching time of 75 min, and temperature of 75 °C. The effect of mechanical activation on Zn leaching was further investigated. The leaching efficiency increased to 90.1% after mechanical activation, which was the highest leaching efficiency for organic acid leaching. Mineralogical characterization showed that the bulk minerals were milled into small particles while the proportion of amorphization increased. Such activation effects improved the acid-solubility of Zn speciation. This work provided a potential green method for metal recovery from low-grade sources.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
