Electrolytic preparation of lanthanide and actinide hexaborides using a molten, cryolite-base electrolyte

Lanthanide and actinide hexaborides are electrolytically synthesized using a molten salt electrolyte containing a major portion of cryolite and minor portions of an alkali borate and a source compound to supply the lanthanide or actinide metal. Minor amounts of an alkali hydroxide or carbonate added to the electrolyte tend to improve product recovery and purity. The synthesis may be accomplished in a cell open to the atmosphere to produce highly pure lanthanide and actinide hexaborides. (auth)