Preparation method of manganous oxide with ultralow calcium, magnesium and heavy metal impurity concentrations

The invention discloses a preparation method of manganous oxide with ultralow calcium, magnesium and heavy metal impurity concentrations. The preparation method comprises the steps of (1) chemical subtraction purifying, (2) anode electrolytic purifying and (3) thermal recovery. Prepared high-purity manganous oxide can be served as raw material for further preparing high-purity manganese compound and high-purity manganese metal. According to the method, the concentrations of calcium and magnesium impurity are reduced to be a very low level (Ca is smaller than or equal to 1ppm, and Mg is smaller than or equal to 3ppm based on MnSO4H2O), simultaneously also has obvious purifying effects on heavy metal impurities such as nickel, cobalt, zinc, copper, cadmium and the like, in the manganese compound, and the flow is simple, the environment is friendly, the method is applicable to mass industrialized production, and the preparation method is efficient for preparing high-purity manganese compound and high-purity mang