I  U  P  A  C




News & Notices

Organizations & People

Standing Committees




. . CI
. . PAC
. . Macro. Symp.

. . Books
. . Solubility Data



Links of Interest

Search the Site

Home Page


Pure Appl. Chem. 74(10), 1909-1920, 2002

Pure and Applied Chemistry

Vol. 74, Issue 10

Solid–liquid equilibria in mixtures of molten salt hydrates for the design of heat storage materials*

W. Voigt and D. Zeng

TU Bergakademie Freiberg, Leipziger Strasse 29, D-09596 Freiberg, Germany

Abstract: Enthalpy of melting can be used to store heat in a simple way for time periods of hours and days. Knowledge of the solid –liquid equilibria represents the most important presumption for systematic evaluations of the suitability of hydrated salt mixtures. In this paper, two approaches for predicting solid–liquid equilibria in ternary or higher component systems are discussed using the limited amount of thermodynamic data available for such systems. One method is based on the modified Brunauer–Emmett–Teller (BET) model as formulated by Ally and Braunstein.

In cases of a strong tendency toward complex formation of salt components, the BET model is no longer applicable. Reaction chain models have been used to treat such systems. Thereby, the reaction chain represents a method to correlate step-wise hydration or complexation enthalpies and entropies and, thus, reduce the number of adjustable parameters. Results are discussed for systems containing MgCl2, CaCl2, ZnCl2, and alkali metal chlorides.

* Lectures presented at the 10th International Symposium on Solubility Phenomena, Varna, Bulgaria, 22 -26 July 2002. Other lectures are published in this issue, pp. 1785-1920.

Page last modified 11 December 2002.
Copyright © 2002 International Union of Pure and Applied Chemistry.
Questions or comments about IUPAC, please contact, the Secretariat.
Questions regarding the website, please contact web manager.