The pyrochemical conditioning of spent nuclear fuel for the purpose of final disposal is currently being demonstrated at Argonne National Laboratory (ANL). One aspect of this program is to develop a lithium preprocessing stage for the Fuel Conditioning Facility (FCF). Furthermore, a pilot scale of this preprocessing stage is being designed by ANL-W to demonstrate the in situ hot cell capability of this process. In this pilot scale system, fused lithium chloride salt is saturated with molten lithium to form a powerful fluxing compound with a vigorous reducing agent. During this stage of the fuel conditioning, the reduction will take place at a nominal temperature of 650 C in an argon-cell atmosphere contaminated with up to 10,000 ppm nitrogen, 100 ppm oxygen and 100 ppm of moisture. The maximum local temperature was calculated to be 725 C on the inner shell of the reduction vessel during operation. One of the significant concerns of this project is the system`s corrosion response in the presence of irradiated commercial fuel as well as atmospheric impurities. The purpose of this work was to demonstrate the potential corrosivity of the salt matrix in a worse case environment as well as provide a boundary for allowable impurities in the system during operation
