Nuclear Fuel Cycle...(see link)
Note that the U.S. is looking into 'Non-Aqueous' "Pyro-Processing" for our closed cycle approach and that is currently being funded...also based on previous work that was done on 'EBR-II' as part of the IFR program (you can Google it if you're interested).
Link: https://www.iaea.org/newscenter/news/frances-efficiency-in-the-nuclear-fuel-cycle-what-can-oui-learn