|About this Abstract
||MS&T22: Materials Science & Technology
||Thermodynamics of Materials in Extreme Environments
||Enthalpy of Mixing of LaCl3 − LiCl:KCl Pseudo Binary Molten Salt System
||Vitaliy G. Goncharov, Jeffrey Eakin, Jiahong Li, Qiang Zhang, Cornelius Ivory, James Boncella, Jason Lonergan, Hongwu Xu, Xiaofeng Guo
|On-Site Speaker (Planned)
||Vitaliy G. Goncharov
LiCl:KCl molten salt eutectic (58 mol. % LiCl − 42 mol. % LiCl) has emerged as an effective medium for pyrochemical processing of spent metallic nuclear fuels. However, the thermodynamic effects of fission by-products (e.g., trivalent La) and tetravalent U within the molten LiCl-KCl eutectic systems remain unclear. In this work we report experimentally measured molar enthalpies of mixing (ΔHmix) for the LaCl3 − LiCl:KCl and UCl4 − LiCl:KCl pseudobinary systems. The mixing energetics for both systems demonstrate irregular mixing behavior with minimums occurring within the alkali rich regions (< 50 mol. % Ln/An). The results of this work suggest that the magnitudes of mixing interactions stemming from dispersion forces and polarizabilities dominate the energetic landscape, while the formation of associate Ln/An-Clx polyhedra contributes to the observed nonlinearity of the interaction parameter (λ) curve within the LiCl-KCl compositionally dominant region.