Method for preparing manganous-manganic oxide material for soft magnetism by using manganese by-product

The invention discloses a method for preparing a manganous-manganic oxide material for a soft magnet by using a manganese byproduct, relates to the technical field of preparation of the manganous-manganic oxide material for the soft magnet, and aims to solve the problem that the cost of preparing the manganous-manganic oxide material for the soft magnet by using an existing method is relatively high. The method comprises the following steps: by taking a manganese byproduct manganese sulfate solution of the manganese-iron alloy flue dust as a raw material, adding quantitative ammonium bicarbonate into the manganese byproduct manganese sulfate solution, and filtering and separating to obtain a manganese carbonate material; drying and roasting the manganese carbonate material to obtain mixed-phase manganese oxide; putting the mixed-phase manganese oxide into a grinding device, adding an organic acid solution, stirring and grinding; after the grinding is finished, washing and filtering the obtained material to ob