Based on work directed by Prof. Sadoway at Sadoway Labs Foundation we obtained first indication of proof-of-concept for conversion of samarium oxide into primary metal by molten borate electrolysis.

Consider a process in which samarium oxide (Sm2O3) which is found in rare earth ores is dissolved in a solvent composed of a solution of metal oxides into which are immersed two electrodes. By the action of electric current samarium oxide is decomposed into liquid samarium which pools on the bottom of the cell and into oxygen which is ducted through the top of the cell. No conversion to chloride which requires carbochlorination resulting in generation of dioxins as by-products. Separating rare earth metals from one another is extremely difficult owing to their nearly identical chemistries: nearly identical electronic structures which means nearly identical chemical behaviors. Separation of target metal which is the basis for refining to high purity resorts to a variety of techniques: some electrochemical, e.g., elecyrorefining by Hoopes-Gadeau, some pysico-chemical techniques such as fractional distillation of the vapors of metal halides or metal chalcogenides, or directional solidification for impurity segregation, and others. Each target rare earth metal presents its own set of challenges owing to the specific composition of the ore body which dictates the impurity profile.