30+ years of solvent extraction development for minor actinide separations in Europe

The recycling of irradiated nuclear fuels contributes significantly to the sustainability of nuclear energy production. The well-established PUREX process to separate uranium and plutonium is pivotal to this recycling. Additionally separating and recycling the minor actinides — most notably americium — further contributes to this goal. Internationally, efforts are made to develop novel solvent extraction processes for the separation of americium from irradiated nuclear fuels.
Concepts to separate americium from the PUREX raffinate solution have been developed in Europe for more than three decades within European collaborative projects. Numerous novel extracting agents have been synthesised and screened. Processes have been developed and tested on the lab scale up to a “technical readiness level” of TRL = 5. Depending on the process chemistry applied, schemes each consisting of three, two or one solvent extraction cycles
are required to obtain a pure americium product. Looking at the history of their development, the various solvent extraction processes are briefly introduced and compared against one another.