Revealing the effect of local structure on phase equilibria in binary molten salts

Mikhail A. Kobelev

doi:10.15826/elmattech.2024.3.045

Revealing the effect of local structure on phase equilibria in binary molten salts

Mikhail A. Kobelev

Abstract

Liquidus curves for LiF-KF and LiF-KCl mixtures are calculated from the two-phase technique in the framework of molecular dynamics simulation. The calculated topology of the solid-liquid equilibria is in excellent correspondence with the experimental data. The local structures in liquid LiF-KF and LiF-KCl mixtures are analyzed by the partial structure factors (PSFs) calculations. For the reciprocal mixture LiF-KCl of equimolar composition, the appearance of a significant intensity peak in the region of small k and only a decrease in the height of the principal peaks of the PSFs for lithium-lithium, fluorine-fluorine, and lithium-fluorine pairs is observed. An intermediate range ordering appears for the Li⁺ and F^– ions, which is associated with clustering of these species and is reflected in the s-shape form for the liquidus curve for LiF-KCl mixture.

Keywords

partial structural factors; reciprocal mixture LiF-KCl; molten LiF; molecular dynamics; liquidus curve

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DOI: https://doi.org/10.15826/elmattech.2024.3.045

Copyright (c) 2024 Mikhail A. Kobelev

This work is licensed under a Creative Commons Attribution 4.0 International License.

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