Measurement of Solubility of Metallic Lithium Dissolved in Molten LiCl–Li2O

The solubility of lithium metal in molten LiCl–Li2O mixtures has been measured at various concentrations of Li2O ranging from 0 wt.% to 2.7 wt.% at a temperature of approximately 670–680°C. After contacting molten lithium with molten LiCl–Li2O for several hours to achieve equilibrium saturation, samples were taken by freezing the salt onto a room-temperature steel rod and dissolving in water for analysis. Both volume of hydrogen gas generated and volume of titrated HCl were measured to investigate two different approaches to calculating the lithium concentration. There appeared to be no effect of Li2O concentration on the Li solubility in the salt. But the results vary between different methods of deducing the amount of dissolved Li. The H2 collection method is recommended, but care must be taken to ensure all of the H2 has been included.