Join the Nuclear Engineering program for light refreshments and a discussion lead by Dr. Supathorn Phongikaroon from Virginia Commonwealth University.
Since the 1950s, special attention has been focused on the use of molten salts in other applications such as batteries, solar energy, and chemical processing. The beneficial features of a high thermal capacity, good heat transfer characteristics, and a strong resistance to the effects of radiation in high-enriched and high-burnup nuclear fuels have led to the use of molten salts in nuclear reactor designs and other nuclear-related applications. One promising potential of utilizing molten salt system is the treatment of used nuclear fuel, known as pyroprocessing technology. At the heart of this process lies an electrorefiner (ER), which electrochemically dissolves uranium from the used fuel at an anode and deposits it on a cathode. Through normal operation of the ER, transuranic elements (such as plutonium and uranium), fission product chlorides and rare earth chlorides accumulate in the molten salt electrolyte (LiCl-KCl) over time. These contaminants change the physical properties of the salt, which influences the overall efficiency of the separation process. Thus, from an operational perspective, it is paramount that exact compositional information is available on the salt in order to adjust and ensure a proper operation. In addition, buildup of transuranic elements in the salt presents criticality and safeguard concerns; this only increases the need for precise concentration data from the salt. This presentation provides the progress on research and development of molten salt projects that are significant for this reprocessing technology. The focus areas will be on (1) development of near real time concentration detection via laser-induced breakdown spectroscopy (LIBS), (2) electrochemical studies on ternary salt systems (e.g., UCl3-LiCl-KCl) for physical and electrochemical property measurements and morphology, and (3) an artificial neural network on existing electrochemical data sets for a smart signal detection analysis. These research areas show significant advancements, which can impact, improve the process basis of the nuclear fuel cycle, and help enabling nuclear safeguards toward the pyroprocessing technology.