Oxidation State Favorability Due to Cation Radii in Molten Salt Reactor Fuel Systems
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2025-07-11 |
| Journal | ECS Meeting Abstracts |
| Authors | Hannah K. Patenaude, Jarom Chamberlain, Kendrich O. Hatfield, Stephen S. Parker, Marisa J. Monreal |
Abstract
Section titled āAbstractāThe extreme conditions of Molten Salt Reactors (MSRs) make even fundamental chemistry challenging for simple salts. However, an operating MSR comprises fission products, corrosion products, and actinides at various concentrations that have yet to be fully described in the literature. The primary objective of this work is to study complex molten salt systems while expanding the evidence for the impacts of solvent salt cation radii on coordination and oxidation state stabilization of species relevant to MSR fuel systems in a range of eutectic solvent salts with varying hardness. Cyclic voltammetry was performed in four solvent salt eutectics (LiCl-KCl, MgCl 2 -NaCl, CaCl 2 -MgCl 2 , and UCl 3 -NaCl) using lanthanide benchmarks as surrogates to inform future Pu experiments. An essential element in ensuring consistency and precision during such measurements is a novel, custom boron-doped diamond electrode for electrochemistry extreme environments. Diamond is known for low background capacitance, rapid electron transfer kinetics, wide potential windows, and resilience in chloride and fluoride molten salts. The present study used BDD to describe Eu 3+/2+ and Ce 4+/3+ via formal potentials, electron transfer kinetics, diffusion, and thermodynamics (ĪG o , ĪH o , and ĪS o ) in the various solvent systems. The success of these measurements informs fundamental chemistry by expanding our understanding of ion interactions in molten salts while characterizing systems applicable to an operating MSR. Additionally, it proves that BDD is an ideal electrochemical sensor for continued measurements in chloride and fluoride molten salts to support the safe, secure deployment of MSRs.