There are two mainstream preparation processes for Mn3O4, namely the manganese metal oxidation method and the manganese sulphate oxidation method.
The manganese metal oxidation method uses electrolytic manganese metal as the raw material. Manganese suspension is prepared through grinding, and air is introduced for oxidation under specific temperature and catalyst conditions. Finally, Mn3O4 is obtained through filtration, washing, and drying processes.
The manganese sulphate oxidation method involves a two-step oxidation process to prepare Mn3O4. First, sodium hydroxide is added to a high-purity manganese sulphate solution to neutralize and produce a precipitate. The precipitate is washed multiple times, followed by an oxidation reaction with oxygen. Subsequently, the precipitate undergoes further washing, filtration, aging, slurry preparation, and drying processes to produce Mn3O4.
Comparing the two processes, Mn3O4 produced by the manganese metal oxidation method has more advantages, mainly in terms of better stability, higher purity, better impurity control, more controllable magnetic substances, and cost advantages. Therefore, this process is extremely important for the accelerated promotion and application of Mn3O4 in manganese-based cathode materials, especially in new-type manganese-based cathode materials.
