Study in reduction-roast leaching manganese from low-grade manganese dioxide ores using cornstalk as reductant

In this study cornstalk was used as reductant for reduction roasting of low-grade manganese dioxide ores, and sulfuric acid was used as leaching solvent for the roasted ore. The effects of weight ratio of ore to cornstalk, roasting temperature, roasting time, ore particle size, leaching temperature, stirring speed and sulfuric acid concentration on the leaching recovery were discussed. The leaching recovery of manganese reached 90.2% under the optimal condition which was determined as manganese dioxide ore to cornstalk weight ratio of 10:3, roasting temperature of 500 °C for 80 min, leaching stirring speed of 400 r/min, sulfuric acid concentration of 3 mol/L, leaching temperature of 50 °C for 40 min.