Thermodynamic Analysis of Preparation of Fe-Si/Fe3Si Intermetallic by Treating Valuable Elements in Red Mud with Molten Salt

Red mud is an alkaline solid wasteWaste generated during the smelting processProcess of bauxite, but its utilizationUtilization rate is low, and there are still billions of tons of red mud that are not effectively treated every year. In this study, the molten saltMolten salt electro-deoxidation processProcess was employed to extract valuable elements from red mud. Based on the characterizationCharacterization results of the red mud raw materialsMaterials, thermodynamic calculations of the reactants in the system were performed using HSC and Factsage thermodynamic calculation software. The results showed that Fe2O3 and SiO2 in the cathode reacted with CaO in the molten saltMolten salt to form Ca2Fe2O5 and Ca2SiO4 before electrochemical reduction due to the rapid electrolytic deoxygenation of Fe2O3, indicating that the reduction processProcess of the Fe component is Ca2Fe2O5/Fe2O3 → Fe3O4 → FeO → Fe; and the reduction processProcess of the Si component is SiO2/Ca2SiO4 → Si.