METHOD FOR REFINING ALUMINUM CHLORIDE-BASED MOLTEN SALT ELECTROLYTE BATH

摘要

PURPOSE:To prolong the service life of an aluminum chloride-based molten salt electrolyte bath by specifying the aluminum chloride content of the bath and removing the precipitated insolubles from the bath. CONSTITUTION:The composition of a two or multiple-component molten salt electrolyte bath contg. aluminum chloride and at least other chlorides such as NaCl is adjusted by heating the bath and so on so that the aluminum chloride content is controlled to <=50mol%. Consequently, the water and metallic impurities in the bath are precipitated on the bottom of a vessel, and the precipitates are drawn off from the bottom and removed. Aluminum chloride is then added to the refined bath to obtain a desired bath composition.