Separation of Actinides from Rare Earth Elements by Electrorefining in LiC1-KC1 Eutectic Salt

Abstract

A pyrometallurgical partitioning technology to recover actinides from high level radioactive wastes is being developed. In the process, actinides are separated from fission products by electrorefining in molten chloride systems. It is expected that REs (rare earth elements), main components of fission products are hardly separated from actinides. In order to estimate separation factors, electrorefining experiments to recover actinides from LiCl-KC1 eutectic salt containing actinide (U, Np, Pu and Am) and RE (Y, La, Ce, Nd and Gd) chlorides were carried out at 450°C. Actinides were removed from a liquid cadmium anode and recovered as metal on a solid cathode. Typical cathode deposits were rough in appearance and contained 70–90wt% adhering salt. The current efficiency was low because some of the deposit occasionally fell from the cathode. It is shown that uranium, neptunium and plutonium are relatively easily separated from REs and that americium is accompanied by some of REs.

KEYWORDS:

• high level radioactive wastes
• pyrometallurgical partitioning
• actinides
• rare earth elements
• molten salts
• LiCl—KCl eutectics
• electrorefining
• solid cathode
• liquid cadmium anode
• separation process