Lab-scale circulation process of electrolytic manganese production with low-grade pyrolusite leaching by SO2

A lab-scale circulation process of electrolytic manganese production with low-grade pyrolusite leaching by SO2 was introduced, exploring its feasibility and stability. Material balances of manganese and sulfur in circulation process were investigated. Results showed that the circulation process was entirely feasible. SO2 absorption efficiency of 99.66% and Mn extraction rate of 95.5% were obtained when a two-stage continuous countercurrent leaching process was used. The electrolytic manganese, meeting the needs of national industry grade standards, could be produced using purified leaching solution. 32 daysʹ continuous running test proved good stability of the circulation process with the current efficiency of 78.1%, electricity consumption of 5396 kW h/t and total Mn recovery rate of 81.77%. The circulation process realized that the electrolytic manganese production with low-grade pyrolusite, has a wide prospect in industrial applications due to the advantages of stable performance, high efficiency and low consumption.