Aluminothermic Reduction of Lunar Soil Simulant Ilmenite in Cryolite Molten Salt Media

Focused on in-situ utilization of lunar resources, we studied the preparation of aluminum alloy by aluminothermic reduction of ilmenite in molten cryolite media. The thermodynamics calculation shows that the standard Gibbs free energy change of aluminothermic reduction of ilmenite is negative in the temperature range 0-1500 ℃. The effects of reductant amount and reaction time on the aluminothermic reduction of ilmenite in 47.14wt%NaF-42.86wt%AlF3-10wt%%FeTiO3 at 960 ℃ were studied. The results obtained by XRF, XRD, SEM and EDS analysis indicate that the products mainly contain Al, Ti, Fe, and a little Si, and the main phase of the product is Al3Ti. With the increase of reductant amount, the content of Ti in alloy products decreases, while the content of Fe in alloy products increases. In addition, the content of Al3Ti increases with the increase of reaction time. The highest content of Ti in the alloy obtained by aluminothermic reaction at 960 ℃ for 2 h using three times reductant amount of theoretical amount is up to 18.82 wt%. Fe and Ti can be separated in FeTiO3 aluminothermic reduction using lower reductant amount and higher reduction time. The FeTiO3 aluminothermic reduction reaction takes place between the dissolved Al atom and dissolved FeTiO3 in the cryolite melt.