Investigation of electrorefining of metallic alloy fuel onto solid Al cathodes

This work concerned the electrorefining of UZr and UPuZr alloys on a solid aluminium cathode, in the LiCl–KCl eutectic melt containing U3+, Pu3+, Np3+, Zr2+ or Zr4+, Am3+, Nd3+, Y3+, Ce3+ and Gd3+ chlorides. During constant current electrolyses, the use of a cathodic cut-off potential (−1.25 V versus Ag/AgCl) allowed to selectively deposit actinides (mainly U), while lanthanides remained in the salt. The aim was to determine the maximal load achievable on a single aluminium electrode. The total exchange charge was 4300 C, which represents the deposition of 3.72 g of actinides in 4.17 g Al, yielding a composition of 44.6 wt% An in Al. It was shown that the melting of the cathode contributed to increase the total amount of actinides deposited on the aluminium.