The molten salt furnace located in the Fuels and Applied Sciences Building west development glovebox is a laboratory-scale system that is used to perform reprocessing research to obtain feedstock (uranium metal and uranium oxide) from spent fuel.
The two most common operations performed using this furnace are oxide reduction and electrorefining. Oxide reduction is an electrochemical method normally performed in a 650°C molten salt composed of LiCl with a small amount of Li2O (~1wt%). During oxide reduction, at the cathode UO2 is electrochemically reduced to U metal liberating O2- ions, which dissolve in the salt and are oxidized to O2 gas at an inert anode. Electrorefining is another electrochemical method, normally performed in a 500°C molten salt composed of LiCl, KCl, and UCl3 (~5 – 10 wt%). In this process, uranium metal is oxidized at the anode to U3+ ions, which dissolve in the salt and are reduced back to U metal and collected at a cathode.
Oxide reduction and electrorefining