About this Abstract |
Meeting |
MS&T24: Materials Science & Technology
|
Symposium
|
Thermodynamics of Materials in Extreme Environments
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Presentation Title |
Electrochemical Determination of Thermodynamic Properties of Ni(II) in FLiNaK Molten Salt |
Author(s) |
Nathan Smith, Stephen Lombardo, Rushi Gong, Jorge Soldan Palma, Hojong Kim, Zi-Kui Liu, Shunli Shang |
On-Site Speaker (Planned) |
Nathan Smith |
Abstract Scope |
Understanding thermochemical properties of common corrosion products (i.e., Ni(II), Cr(II/III) from structural materials used in molten salt reactors is important for developing improved corrosion-resistant materials and in-situ monitoring systems. Electromotive force measurements were employed to determine the activity of Ni(II) in molten FLiNaK salt for a wide range of compositions (<i>x</i><sub>Ni(II)</sub> = 0.001–0.17) and temperatures (<i>T</i> = 723–923 K). Complementary characterization including X-ray diffraction (XRD), inductively coupled plasma atomic emission spectroscopy (ICP-AES), and differential scanning calorimetry (DSC) were used to determine phase behavior and transition temperatures. Experimental results were compared to computational phase models developed via the CALPHAD methodology. The stability of BN in FLiNaK + NiF<sub>2</sub> was also examined due to the frequent use of BN as an insulating material for Ni(II)/Ni reference electrodes in molten fluoride salts. |