Preparation of high-purity manganese carbonate from steel plant dust

Using steel plant dust,manganese carbonate was prepared by reaction of acid-leaching,purification,precipitation and replacement reaction.The effects of the leaching temperature,the leaching time,the mass ratio of sulfuric acid to steel dust on the leaching yield of manganese were investigated by the orthogonal test methods.The optimum leaching conditions were as follows:the mass ratio of sulfuric acid to steel dust 4:1,the leaching temperature 70℃,time 2 h,the leaching yield of manganese was 87.7%.By means of single factor experiments,the optimal carbonization conditions were obtained:n((NH₄)₂CO₃):n(MnSO₄)=2:1,the reaction temperature was 60℃,pH=7,the aging time was 30 min,and the yield of manganese carbonate reached 91%.The prepared manganese carbonate accords with GB10503-89.