Test of Actinide-Lanthanide Separation in an Aluminum-Based Pyrochemical System

The investigation of the actinide and lanthanide distribution between a liquid metal and a molten fluoride salt shows a significant increase of the separation coefficient by using an aluminum-based pyrochemical system instead of a zinc-based system. The obtained values partly depend on the LiF/AlF₃ ratio and can reach more than 30 000 when AlF₃ is in excess with regard to the formation of the cryolite (Li₃ AlF₆). Furthermore, in the metal phase, the aluminum interacts with the lanthanides to a lesser extent than in other usual metallic solvents. This opens a new way to explore the feasibility of the separation of actinides and lanthanides in the field of nuclear fuel reprocessing.