Thermodynamic Assessment of the NaCl-CrCl₂, NaCl-CrCl₃, and FeCl₂-CrCl₂ Pseudo-Binary Systems for Describing the Corrosion Chemistry Between Molten Salt Fuel and Steel

A thorough understanding of the corrosion chemistry between molten salt fuel and structural materials (e.g., steel) is key for the advancement of Molten Salt Reactor technology. In this work, we consider more specifically the case of a chloride fuel salt mixture and the thermochemistry of a salt mixture such as (NaCl-MgCl₂-PuCl<sub...

Correction: Ocádiz Flores et al. Thermodynamic Description of the ACl-ThCl4 (A = Li, Na, K) Systems: Thermodynamic Description of the ACl-ThCl4 (A = Li, Na, K) Systems (Thermo, (2021), 1, 2, (122-133), 10.3390/thermo1020009)

Corrected excess Gibbs energies of the liquid solutions in the ACl-ThCl4 (A = Li, Na, K), as well as revised standard enthalpies of formation and standard entropies of the intermediate phases occurring in the binary systems, are presented. The phase diagrams are reproduced to a similar level of accuracy as in the original publication, and the...

Using the Quasi-chemical formalism beyond the phase Diagram: Density and viscosity models for molten salt fuel systems

CALPHAD models to compute the density and viscosity of four keystone systems related to Molten Salt Reactor (MSR) technology have been optimized: NaCl-UCl₃, LiF-ThF₄, LiF-UF₄, and LiF-ThF₄-UF₄. Revised thermodynamic assessments of all four systems, using the modified quasichemical...

A promising fuel for fast neutron spectrum Molten Salt Reactor: NaCl-ThCl₄-PuCl₃

Chloride salts are considered a good alternative to fluoride salts as fuel carrier in the Molten Salt Fast Reactor concepts. The NaCl–ThCl4–PuCl3 fuel salt solution seems very promising, with low melting temperature eutectic compositions, and the potential to be used in a breeder and burner type of reactor design. This work focuses on the...

New insights and coupled modelling of the structural and thermodynamic properties of the LiF-UF4 system

© 2021 The Authors LiF-UF4 is a key binary system for molten fluoride reactor technology, which has not been scrutinized as thoroughly as the closely related LiF-ThF4 system. The phase diagram equilibria in the system LiF-UF4 are explored in this work with X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The short-range...

Coupled structural-thermodynamic modelling of the molten salt system NaCl-UCl₃

Molten chloride salts are ionic liquids in which the anions and cations exhibit network formation. An attractive salt system for use in molten salt reactors is NaCl-UCl₃, an ionic liquid with complex non-ideal thermodynamic behaviour due to the formation of short-range order. The relationship between local structure and...

Thermodynamic Description of the ACl-ThCl4 (A = Li, Na, K) Systems

The ACl-ThCl (Formula presented.) (A = Li, Na, K) systems could be of relevance to the nuclear industry in the near future. A thermodynamic investigation of the three binary systems is presented herein. The excess Gibbs energy of the liquid solutions is described using the quasi-chemical formalism in the quadruplet approximation. The phase...

Examination of the short-range structure of molten salts: ThF₄, UF₄, and related alkali actinide fluoride systems

The short-range structures of LiF-ThF4, NaF-AnF4, KF-AnF4, and Cs-AnF4 (An = Th, U), were probed using in situ high temperature Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy. Signally, the EXAFS spectra of pure molten ThF4 and UF4 were measured for the first time. The data were interpreted with the aid of Molecular Dynamics ...

Experimental and Computational Exploration of the NaF-ThF₄Fuel System: Structure and Thermochemistry

The structural, thermochemical, and thermophysical properties of the NaF-ThF4 fuel system were studied with experimental methods and molecular dynamics (MD) simulations. Equilibrium MD (EMD) simulations using the polarizable ion model were performed to calculate the density, molar volume, thermal expansion, mixing enthalpy, heat capacity, and...

Thermodynamic assessment of the KF-ThF₄, LiF-KF-ThF₄ and NaF-KF-ThF₄ systems

A thermodynamic assessment of the KF-ThF₄ binary system using the CALPHAD method is presented, where the liquid solution is described by the modified quasichemical formalism in the quadruplet approximation. The optimization of the phase diagram is based on experimental data reported in the literature and newly measured X-ray...

Thermodynamic assessment of the LiF-NiF₂, NaF-NiF₂ and KF-NiF₂ systems

Using the modified quasi-chemical model in the quadruplet approximation, three new thermodynamic assessments of binary systems useful for the detailed operational design of the Molten Salt Reactor are presented: AF-NiF₂ (A = Li, Na, K). These systems are particularly relevant for the study of the molten salt-structural materials...

In situ high-temperature EXAFS measurements on radioactive and air-sensitive molten salt materials

The development at the Delft University of Technology (TU Delft, The Netherlands) of an experimental set-up dedicated to high-temperature in situ EXAFS measurements of radioactive, air-sensitive and corrosive fluoride salts is reported. A detailed description of the sample containment cell, of the furnace design, and of the measurement...