The limits of miscibility in the lithium-potassium system

An investigation of the lithium-potassium system was made over the temperature range 63–500 °C. It was found that between 63 and 180 °C a potassium-rich liquid phase was in equilibrium with solid lithium, while two immiscible liquid phases were present above 180 °C. The solubilities of potassium in liquid lithium and lithium in liquid potassium, as determined by chemical analyses of the immiscible phases sample at temperature, can be represented by the following expressions: log S(Li in K) (wt. ppm) = 6.09−1837T (°K), and log S(K in Li) (wt. ppm) = 5.50−1362T(° K).