An overview of solvent extraction processes developed in Europe for advanced nuclear fuel recycling, part 1 — heterogeneous recycling

ABSTRACT

The hydrometallurgical separation concepts for the heterogeneous recycling of irradiated nuclear fuel developed in Europe are presented and discussed. Most of these concepts were developed within European collaborative projects and involve solvent extraction processes separating trivalent minor actinides (with a focus on americium) from the raffinate solution from processes such as PUREX (Plutonium Uranium Reduction Extraction) or an evolution of PUREX. Depending on the process chemistry applied, process schemes each consisting of one, two or three solvent extraction cycles are required to obtain a pure americium product. The various solvent extraction processes are briefly introduced. The most suitable choices are selected, and the process schemes are compared to one another.

KEYWORDS:

• Nuclear fuel
• heterogeneous recycling
• actinides
• solvent extraction
• processes

Notes

¹ Here we refer to spiked tests as experiments using a simulant solution containing a representative selection of actinides and fission products. Spiked tests may be conducted either with trace or realistic concentrations of actinides; fission products are replaced with the stable elements to avoid high beta/gamma dose rates. Spiked tests can usually be conducted in designated radiochemical fume hoods or glove boxes. Hot tests refer to experiments with dissolved fuels or targets after irradiation in a reactor. These solutions are highly active and require shielded cells due to the beta/gamma radiation levels.

Additional information

Funding

This work has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme [project GENIORS, grant agreement N° 755171].