Metal oxide solubility in eutectic Li/K carbonate melts

The equilibrium solubility of NiO, CuO, ZnO, LiFeO2, and LaNiO3 in binary Li/K carbonate was quantitatively measured between 823 and 1223 K under a simulated molten carbonate fuel cell cathode environment. The solubility of all materials, except LaNiO3, was found to increase with increasing temperature. Equilibrium solubilities at 923 K, the operating temperature of a molten carbonate fuel cell, were determined to be 13 X 10-6, 32 X 10-6, 63 X 10-6, and 16 X 10-6 mole fraction for NiO, CuO, ZnO, and LiFeO2, respectively. The LaNiO3 solubility remained below the quantitative detection limit until the melt's temperature exceeded 1123 K, at which time material decomposition was detected