Microwave-assisted recovery of lead from electrolytic manganese anode sludge using tartaric acid and NaOH

In this study, a new metallurgical system for treating electrolytic manganese anode sludge by microwave roasting and alkaline leaching system was developed, and the lead leaching behaviour was studied. The XRD results show that Pb in anode sludge is mainly in the form of PbSO4 after microwave roasting at 850°C, as a result, the leaching rate of Pb is improved. The results show that the leaching rate of lead can reach 93.89% under the conditions of liquid–solid ratio of 7:1, leaching time of 30 min, leaching temperature of 40°C, and the concentration of sodium hydroxide of 8%. The addition of tartaric acid can further improve the lead leaching rate, FT-IR analysis showed that the coordination form of lead and tartaric acid. Lead and tartaric acid ions (L) form three coordination compounds, PbL, Pb2L2 and Pb2L3, which can only exist in alkaline solution.