[en] In support of the development of pyrochemical separation systems, the equilibrium distributions of actinides and lanthanides were measured in some typical binary phase systems of molten salt and liquid metal. LiF-BeF₂ mixture was selected as the salt phase, and Bi, Sn, Cd and Zn were examined as the metal phase. Actindes were more easily reduced and extracted from the salt phase into the metal phase than lanthanides. The group partitioning was thus feasible. In different metal phase systems, different separation factors between actinides and lanthanides were observed. (author)