A review of the demonstration of innovative solvent extraction processes for the recovery of trivalent minor actinides from PUREX raffinate

摘要

The selective partitioning (P) of long-lived minor actinides fromhighly active waste solutions and their transmutation(T) to short-lived or stable isotopes by nuclear reactions will reduce the long-term hazard of the high-level waste and significantlyshorten the time needed to ensure their safe confinement in a repository. The present paper summarizes the on-going researchactivities at Forschungszentrum Jülich (FZJ), Karlsruher Institut für Technologie (KIT) and Institute for TransuraniumElements (ITU) in the field of actinide partitioning using innovative solvent extraction processes. European research overthe last few decades, i.e. in the NEWPART, PARTNEW and EUROPART programmes, has resulted in the development ofmulti-cycle processes for minor actinide partitioning. These multi-cycle processes are based on the co-separation of trivalentactinides and lanthanides (e.g. by the DIAMEX process), followed by the subsequent actinide(III)/lanthanide(III) groupseparation in the SANEX process. The current direction of research for the development of innovative processes within therecent European ACSEPT project is discussed additionally. This paper is focused on the development of flow-sheets forrecovery of americium and curium from highly active waste solutions. The flow-sheets are verified by demonstration processes,in centrifugal contactors, using synthetic or genuine fuel solutions. The feasibility of the processes is also discussed.