ABSTRACT

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 interaction, as the salt containment is made of a Ni-based alloy. Using powder X-ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC), new experimental data were gathered for two of these systems, LiF-NiF2 and KF-NiF2, and compared to previous experimental assessments. Our data have confirmed the formation of a (Li1-2xNix)F solid solution. The three thermodynamic models show a very good agreement with the experimental data. The melting point of NiF2 was measured for the first time to be T = (1629 / 5) K, and the thermal expansion coefficient for Li2NiF4 was found to be /=27.6*10-6K-1 in the temperature range T = (298 -773) K.

Compounds

#	Formula	Name
1	F2Ni	nickel difluoride
2	FLi	lithium fluoride
3	FK	potassium fluoride
4	F4Li2Ni	lithium nickel fluoride (Li2NiF4)
5	F3KNi	nickel potassium fluoride (KNiF3)

Datasets

The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type	Compound-#	Property	Variable	Constraint	Phase	Method	#Points
POMD	1	Normal melting temperature, K ; Crystal			Crystal Liquid Air at 1 atmosphere	DTA	1
POMD	1	Mass density, kg/m3 ; Crystal	Temperature, K; Crystal Pressure, kPa; Crystal		Crystal	X-ray diffraction	1
POMD	2	Normal melting temperature, K ; Crystal			Crystal Liquid Air at 1 atmosphere	DTA	1
POMD	2	Mass density, kg/m3 ; Crystal	Temperature, K; Crystal	Pressure, kPa; Crystal	Crystal	X-ray diffraction	7
POMD	3	Normal melting temperature, K ; Crystal			Crystal Liquid Air at 1 atmosphere	DTA	1
POMD	3	Mass density, kg/m3 ; Crystal	Temperature, K; Crystal Pressure, kPa; Crystal		Crystal	X-ray diffraction	1
POMD	4	Mass density, kg/m3 ; Crystal	Temperature, K; Crystal	Pressure, kPa; Crystal	Crystal	X-ray diffraction	5
POMD	5	Normal melting temperature, K ; Crystal			Crystal Liquid Air at 1 atmosphere	DTA	1
POMD	2 1	Quadruple (quintuple) point temperature, K ; Crystal of intercomponent compound 1			Crystal of intercomponent compound 1 Crystal - 1 Crystal Air at 1 atmosphere	DSC	1
POMD	2 1	Solid-liquid equilibrium temperature, K ; Crystal	Mole fraction - 1; Crystal	Pressure, kPa; Crystal	Crystal Liquid	DTA	4
POMD	1 3	Eutectic temperature, K ; Crystal - 3			Crystal - 3 Crystal of intercomponent compound 2 Liquid Air at 1 atmosphere	DTA	1
POMD	1 3	Peritectic temperature, K ; Crystal of intercomponent compound 2			Crystal of intercomponent compound 2 Crystal of intercomponent compound 1 Liquid Air at 1 atmosphere	DTA	1
POMD	1 3	Solid-liquid equilibrium temperature, K ; Liquid	Mole fraction - 1; Liquid	Pressure, kPa; Liquid	Liquid Crystal of intercomponent compound 1	DTA	2

Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

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

Ocadiz-Flores, J.A., Capelli, E., Raison, P.E., Konings, R.J.M., Smith, A.L.

ABSTRACT