A New Method for Preparing Hydroxide-Free Alkali Chloride Melts

Abstract

Molten salts have been used extensively as solvents for electrochemical processes. The difficulty of removing the last traces of residual moisture from the salts has often necessitated rather arduous drying procedures. If the moisture is not removed, hydrolysis occurs upon fusion. The hydroxide ion thus produced precipitates metal ions, attacks glass, and is reduced more easily than the alkali metals, thus diminishing the usable potential range of the solvent. It was found that if rigorously dried hydrogen chloride is bubbled through the melt for twenty minutes before the argon flush, the hydroxide ion impurity is removed.