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 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 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 in the temperature range T = (298–773) K.

OCADIZ-FLORES Jaen Alonso;  CAPELLI Elisa;  RAISON Philippe;  KONINGS Rudy;  SMITH Anna; 

2018-02-16

ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD

JRC107680

0021-9614,   

https://publications.jrc.ec.europa.eu/repository/handle/JRC107680,   

10.1016/j.jct.2018.01.023,