Study On Electrolytic Manganese Anode Slag About Impurities' Morphology And Removal Mechanism

Electrolytic manganese anode slag is a dark brown byproducts generated in the EMM anode. changes The structure and properties of slag was changed in the electrolysis process so that chemical activity is reduced.Manganese anode slag, having rich lead,is a highly toxic hazardous waste. In the past, Manganese anode slag was sold by he metal manganese manufacturer at low prices to ferroalloy plant for smelting ferromanganese and silicomanganese alloy, but lead pollution was easily ocuured in production processes, and caused serious environmental pollution. Therefore, it is very important significance for recycling to study on the formation mechanism,shape and impurities removal of electrolytic manganese anode slag.In the anode slag,manganese's content is 46.42%, manganese's form is mostly tetravalent manganese approaching ?-MnO2 which is product Mn2+ is oxidized in electrolyte.Lead,an amount of 5.19% in slag,is produced after the anode plate dissolved and deposited.In the form,PbSO4 is main, manganese lead compounds occupies a small amount.The crystals of the electrolyte is main in the remaining composition of slag.Manganese anode slag contains three categories impurities,water-soluble impurities in it is removed in the wet ball mill grinding process. Acid-soluble impurities is removed by sulfuric acid solution.the process is influenced in the amount of sulfuric acid, time, temperature and liquid-solid ratio,and the amount of sulfuric acid and liquid-solid ratio is major influences. To 50 g slag,the optimum conditions of removing acid-soluble impurities is the amount of sulfuric acid at 15 ml, room temperature, reaction time at 40 min and liquid-solid ratio at 4: 1. After these, manganese content reached to 50.19%, manganese dioxide content reached to 79.42%.The part of PbSO4 in the insoluble lead impurities can be removed by acetic acid-sodium acetate buffer solution. The process is influenced in the amount of lead leaching agent, time, temperature and liquid-solid ratio,and the amount of lead leaching agent and temperature is major influences. To 50 g slag,the optimum conditions of removing PbSO4 impurities is pure lead leaching agent, temperature at 90?, reaction time at 40 min and liquid-solid ratio at 5: 1. After these, it is obtained to rich- manganese products of manganese at 56.89%, manganese dioxide content at 90.03%, lead content about 0.44%.