Pyrochemical Reprocessing of Spent Fuel by Electrochemical Techniques Using Solid Aluminium Cathodes

Pyrochemical methods for reprocessing of spent nuclear fuel are under development as an alternative to the hydrometallurgical processes. The pyrochemical reprocessing process developed in ITU is based on electrorefining of spent fuel in molten LiCl-KCl salt using solid aluminium cathodes. This is followed by a chlorination process for the recovery of actinides from the actinide-aluminium alloys formed and exhaustive electrolysis is proposed for clean-up of the salt from the remaining actinides. In this paper, all investigated techniques are described and the main achievements are summarised. The emphasis is given to the electrorefining, which represents the core process for homogeneous recovery of all actinides from the spent fuel. High efficiency of the process and excellent recovery of actinides over lanthanides have been achieved and very high capacity of solid aluminium to take up actinides has been demonstrated.