Isotope Effect of Cation Electromigration in Molten Lithium Chloride-Nitrate-Mixtures

Abstract

Abstract Molten mixtures of lithium chloride and nitrate, including the decomposition products nitrite and oxide, were electrolysed at about 600 °C with gaseous electrodes. The relative mobilities of the lithium isotopes were studied. The mass effect (relative difference in mobility divided by relative difference in mass) is 0.063 for a mixture with 20% Cl- and 0.069 for 80% CI-, which both are more than 30% smaller than those interpolated from the isotope effects of pure LiNO3 and LiCl. It is concluded that the lithium ions interact more strongly (with the anions and/or with each other) in a melt containing several anions than in a pure melt. The experiments also yield some information about the mobilities of the anions present in the melt.