Equilibrium Distributions of Actinides and Lanthanides in Molten Salt and Liquid Metal Binary Phase Systems

In support of the development of a pyrochemical group partitioning process of actinides and lanthanides, the equilibrium distributions of these elements were measured in some binary phase systems of molten salt and liquid metal. LiF-BeF_2 mixture was selected as the salt phase, and Bi, Sn, Cd and Zn were examined as the metal phase. In general, actinides were more easily reduced and extracted from the salt phase into the metal phase than lanthanides. The group partitioning is thus feasible. In different partitioning systems, systematic difference in the separation factor between actinides and lanthanides was observed. The difference is attributable to the difference in alloying energies in the metal phase