Sustainable Mining and Metallurgy

Aiming at the reduction leaching solution of zinc anode slime in wet zinc smelting, battery grade manganese sulfate (qualified product) was prepared by iron jarosite method to remove potassium and sodium, neutralization and hydrolysis to precipitate iron, manganese fluoride to remove calcium and magnesium, hydrogen sulfide to remove heavy metals, and evaporation-concentration-crystallization method. The single factor experiment was carried out to investigate the influence of step-by-step purification process conditions. The results showed that the concentration of potassium, sodium, calcium and magnesium in the solution was less than 60mg/L, the concentration of iron ion was less than 1mg/L, and the concentration of heavy metal lead and zinc was less than 5mg/L under the conditions of the molar ratio of iron to potassium and sodium was 5, the pH of neutralization hydrolysis precipitation of iron was 4.0, the excess coefficient of manganese fluoride was 1.4, hydrogen sulfide dosage was 0.2 mol, and the temperature was 60-97℃. The solution was stirred in a water bath for 4-6h and then evaporated and crystallized. The obtained crystal product was baked at 105℃ for 12h to obtain a manganese sulfate monohydrate product. Its chemical composition meets the standard requirements. The product was characterized by XRD and SEM-EDS. The results show that manganese sulfate monohydrate has high purity, concentrated particle distribution, rough surface but no floccules.