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Lu, X., Zou, X., Li, C., Zhong, Q., Ding, W., & Zhou, Z. (2012). Green Electrochemical Process Solid-Oxide Oxygen-Ion-Conducting Membrane (SOM): Direct Extraction of Ti-Fe Alloys from Natural Ilmenite. Metallurgical and materials transactions b-Process metallurgy and materials processing science, 43 (3), 503-512.The direct electrochemical extraction of Ti-Fe alloys from natural ilmenite (FeTiO3) in molten CaCl2 is reported in this article. The sintered porous pellet of natural ilmenite acted as the cathode of the electrochemical system, and the carbon-saturated liquid tin contained in a solid-oxide oxygen-ion-conducting membrane (SOM) tube served as the anode of the electrolytic cell. The electrochemical process was carried out at 3.8 V, under 1223 K and 1273 K (950 A degrees C and 1000 A degrees C). Oxygen was ionized continuously from the cathode and discharged at the anode; solid porous Ti-Fe alloys were obtained at the cathode. The electro-deoxidation procedure of the ilmenite was characterized by analyzing partially electro-deoxidized samples taken periodically throughout the electro-deoxidation process. The findings of this study are as follows: (1) The electro-deoxidation process followed these steps: Fe2TiO5 -> FeTiO3 -> Fe2TiO4 -> Fe, Ti (and/or Ti-Fe alloys); and TiO2 -> CaTiO3 -> Ti; and (2) two types of particle growth pattern are observed in the experiments. The first pattern is characterized with particle fusion and second pattern is interconnection of particles to form porous structure. A microhole oxygen-ion-migration model is suggested based on the experimental evidence.Peer reviewe

silicide has been extracted directly from complex multicomponent Ti/Si-containing metal oxide compounds by electro-deoxidation in molten calcium chloride using an inert solid oxide oxygen-ionconducting membrane (SOM) based anode. Studies on the microstructure evolution and electrochemical extraction mechanism show that the formation of Ti 5 Si 3 and the removal of impurity elements happened simultaneously during the electro-deoxidation process. It is found that the electro-deoxidation generated Ti 5 Si 3 micro-particles typically possess a smooth surface, which could contribute to create a continuous anti-oxidation surface layer with excellent high-temperature oxidation resistance property.Consideration is also given to the parameters of electrolysis and the electrochemical characteristics including chemical and/or electrochemical reactions during the electro-deoxidation process, and then a relevant kinetic model is proposed.