12/11/2024
By Danielle Fretwell
Candidate Name: Anthony Bowers
Degree: Doctoral
Defense Date: Wednesday, December 18, 2024
Time: 9:45 a.m. - 12:45 p.m.
Location: Please email the advisor or student for Zoom link.
Committee:
Advisor: Subash L. Sharma, Assistant Professor, Department of Chemical Engineering, University of Massachusetts Lowell
Committee Members*
Dongming Xie, Assistant Professor, Department of Chemical Engineering, University of Massachusetts Lowell
Jerome Delhommelle, Assistant Professor, Chemistry, University of Massachusetts Lowell
Thomas F. Fuerst, Research Scientist, Fusion Safety Program, Idaho National Laboratory
Brief Abstract:
In the MSRs, lithium-based molten salts, FLiBe (66.7% LiF, 33.3% BeF₂) and FLiNaK (46.5% LiF, 11.5% NaF, 42% KF), have the potential to advance the fission industry by elevating operating temperatures, the possibility of processing waste during operation, and operate at a lower pressure. While in fusion reactors, lithium-based fluids, like molten salts and molten metals (LiPb (15.7% Li, 84.3% Pb)), serve as the breeder material to sustain the tritium-deuterium reaction in the fuel cycle.
However, these lithium-based fluids serve as a limiting factor for further advancements due to the challenges presented by the generated radionuclide, Tritium. Tritium is a radioactive nuclide with a half-life of 12.3 years, found in trace amounts in the atmosphere. It is primarily produced through neutron reactions with lithium-6 (Li-6) in the thermal neutron spectrum and lithium-7 (Li-7) in the fast neutron spectrum. Tritium poses significant challenges due to its uncertainty in transport phenomena. When generated in molten salt, tritium will combine with the fluoride ion to form tritium-fluoride (TF), leading to the corrosion of structural materials. Conversely, if no fluorides are present, neutral tritium (T0) will combine and form molecular tritium (T2), which can permeate through hot structural materials. Thus, there is a high interest in developing tritium control and extraction technologies.
The transport of tritium must be fully understood to develop and design cost-effective and impactful complete tritium control and extraction technologies. Thus, this thesis investigates the gaps within tritium transport, current and previous experimental efforts of tritium extraction, and modeling efforts to develop a strategic research plan that best addresses these issues.