Details

Autor(en) / Beteiligte

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

Titel

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

Ist Teil von

• The Journal of chemical thermodynamics, 2018-06, Vol.121, p.17-26

Ort / Verlag

Elsevier Ltd

Erscheinungsjahr

2018

Link zum Volltext

Quelle

Elsevier ScienceDirect Journals Complete

Beschreibungen/Notizen

• •CALPHAD models are reported for the LiF-NiF2, NaF-NiF2 and KF-NiF2 systems, which reproduce well the experimental data.•The melting point of NiF2 is reported at T = (1629 ± 5) K.•The existence of a Li1-2xNixF solid solution in the LiF-NiF2 system has been confirmed by DSC and high temperature XRD.•The thermal expansion coefficient of Li2NiF4 derived by high temperature XRD is α=27.6·10-6K-1 in the range T = (298–773) K. 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 α=27.6·10-6K-1 in the temperature range T = (298–773) K.