Electrolytic reduction of mixed (Fe, Ti) oxide using molten calcium chloride electrolyte

The production of high-purity metals or alloys using effective technologies is critical for future industrialization. With this aim in mind, a fundamental study of electrolysis in molten CaCl₂ electrolytes was conducted to develop a new production process for ferrotitanium (Fe-Ti) intermetallic alloys. Mixed solid oxides of TiO₂ and Fe₂O₃ were used in a molar ratio of 5.44:1.00. In this composition of Ti and Fe, FeTi and β-Ti containing iron can co-exist in equilibrium. A mixed solid (Fe, Ti) oxide was reduced electrochemically in a molten CaCl₂ electrolyte at 950 °C. The metallic samples formed by electrolytic reduction of the mixed solid (Fe, Ti) oxide were analyzed using X-ray diffraction, scanning electron microscopy/energy-dispersive X-ray spectroscopy, electron-probe microanalysis, X-ray fluorescence spectrometry, inductively coupled plasma atomic emission spectroscopy, ion chromatography, and oxygen and carbon analyzers. The oxide pellets were successfully reduced to a highly purified dense intermetallic solid of β-Ti (FeTi₄) and FeTi containing low levels of impurities, for example, less than 0.01 mass% of carbon.