RT2: Speciation and Redox Processes in Molten Salt Environments
Thrust 2 investigates how dissolved species — actinides, fission corrosion products, nanoparticles, and impurities — together with radiation-driven redox processes, shape the chemistry of molten salt environments.
Scientific Focus
Molten salt reactor environments bring together concentrated salts, dissolved fuel constituents, fission and corrosion products, as well as impurities — all affected by radiation-driven chemistry. Thrust 2 focuses on how these components exist and react in the melt: which chemical forms are present, how soluble they are, how they interact with the surrounding salt, and how those interactions shape the chemical behavior and reactivity of the system.
These questions are central to both fundamental molten salt chemistry and the practical challenges of molten salt reactor technologies. The principles governing phase behavior and reactivity of complex salt mixtures are intertwined with speciation and the structure of the melt.
In reactor-relevant systems, the challenge is amplified by high actinide loadings, changing fission-product inventories, corrosion products, impurities, and the effects of ionizing radiation on redox chemistry. MSEE is especially well positioned to address these problems by leveraging the team's unique expertise to synthesize, purify, handle, and characterize actinide-containing molten salts. The access to such specialized capabilities allows Thrust 2 to study chemically complex systems that are relevant to nuclear energy applications while developing the molecular-level understanding needed to make their behavior predictable.
Approach and Impact
Thrust 2 combines molecular simulations with targeted experimental measurements to determine how solutes behave in molten salts and how those solutes change the reactivity and properties of the melt. The work connects local coordination structure with macroscopic properties such as solubility, redox behavior, thermal properties, and overall chemical reactivity.
The thrust emphasizes three connected questions: (i) how temperature and salt composition control the speciation of dissolved solutes; (ii) how solutes such as metal ions and nanoparticles interact with molten salts to affect solubility, thermal properties, and chemical reactivity; and (iii) how radiation drives redox processes and alters metal-ion speciation in molten salt environments.
The resulting knowledge supports a more quantitative understanding of corrosion processes, fission-product behavior, actinide-containing fuel salt chemistry, radiation-induced redox chemistry, and impurity effects. In turn, this work helps provide the scientific basis for controlling molten salt chemistry in advanced nuclear energy systems.
Thrust 2 Aims
Chemistry, solubility, and fate of solutes (minor components) in molten salts
Elucidate solute speciation and solubility as a function of temperature and solvent composition.
Radiation-induced effects — nanoparticle formation, aggregation, stability, and interaction with neighboring species in molten salts
Investigate radiolytic transients and nanoparticle formation in the context of their stability and their effects on molten salt properties.
Effects of the presence of solutes on the chemical reactivity of the melt
Elucidate the relationship between solute speciation and chemical reactivity by investigating solute behavior as a function of optical basicity, redox poise, and the charge-transfer characteristics of solvent salts.
