b'Proof of Principle ExperimentsThis research expands knowledge in molten salt technologies and benefits for a Pyrochemical Approach toinnovative fuel cycle science.Treatment of Used AdvancedT he goal of this research was to substantiate a novel pyrochemical process applicable to treatment of used Advanced Test Reactor fuel to facilitate its Test Reactor Fuel recycle and disposition. This process involves chemical and electrochemical methods to separate and recover highly enriched uranium from the used fuel into a purified high-assay low-enriched uranium metal form.This research focused on fuel dissolution and separation of its aluminum matrix and cladding. To provide a rapid demonstration of this step, neodymium metal was used TOTAL APPROVED AMOUNT:as a non-radiological surrogate for uranium metal. Thus, the specific objective of this $125,000 over 1 year study was to demonstrate and characterize the dissolution of neodymium metal into a molten halide salt system while simultaneously removing aluminum as a volatile PROJECT NUMBER:halide. Accordingly, aluminum metal particulate and foil (representing aluminum 20A1047-039 matrix and cladding, respectively) along with neodymium metal particulate were PRINCIPAL INVESTIGATOR:blended at bench scale with either ammonium chloride or bromide (halogenating Steven Herrmann agents) and lithium chloride or bromide, respectively, and heated. Ammonium halides decomposed into ammonia and hydrogen halides, the latter of which CO-INVESTIGATORS: reacted with aluminum and neodymium metal to form their respective halides. The Michael Patterson, INL relatively high vapor pressures of aluminum halides drove their gaseous separation Steven Frank, INL from the neodymium halides, which fused with their respective lithium halides. The demonstration yielded excellent separation of the metals with 98.2% and 97.8% of the loaded aluminum separating as volatile chlorides and bromides from their respective molten salt systems, while no neodymium or lithium halides were detected in their respective aluminum halide streams. Thus, this work proved the principle that aluminum metal can be effectively separated from neodymium metal via halogenation and volatile specie collection.TALENT PIPELINE:Steven Herrmann, student at University of IdahoPUBLICATION:Herrmann, S. D., H. Zhao, M. Shi, M. M. Jones, and M. N. Patterson, Halogenation of used aluminum matrix test reactor fuela bench-scale demonstration with surrogate materials, Journal of Nuclear Science and Technology 59(3) (2021) 395406.Simplified sectional view of the furnace and off-gas trap assembly for series of halogenation and waste-form runs (a). Waste-form blend before (b) and after (c) consolidation.66'