Reactivity of Manganese Sulphate from Sumbawa Manganese Ore with Precipitating Agent: Theoretical and Experimental Evaluation

Abstract

Manganese oxide (Mn3O4) was successfully synthesized from manganese sulphate using co-precipitation method. The manganese sulphate recovered from Sumbawa manganese ore. In order to predict the manganese oxide product, the Gibbs free energy calculation was performed for the possible reaction between MnSO4 and NaOH. The experimental results showed that the manganese oxide product was Mn3O4, which is consistent as the calculated Gibbs free energy is the lowest among other products. No secondary phase such as MnO, MnO2 or Mn2O3 were found in the X-ray diffraction analysis. However, Mn3O4 had coarse particle size, i.e., 1669 ± 431 nm, which is not the type of co-precipitation's results. Therefore, further study is needed to obtain fine particle size of Mn3O4.