Poster (After Call)

FZJ-2022-02833

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Experimental study and thermodynamic assessment of Li2CO3-K2CO3

Qi, J. (Corresponding author)FZJ* ; Sergeev, D.FZJ* ; Yazhenskikh, E.FZJ* ; Ziegner, M.FZJ* ; Müller, M.FZJ*

2022

Abstract: The salts Li2CO3 and K2CO3 are widely used in molten carbonate fuel cell and Electrochemical Deposition of Carbon Materials. Because of their high energy density, they are also good candidates for heat storage in concentrated solar power plants. As the thermodynamic data on these carbonates and the binary system in the commercial database is inaccurate, they are being reinvestigated in this work. Using high temperature X-ray diffraction, it was found out that the previously reported solid-solid phase transition [3, 4] of Li2CO3 was caused by impurity of LiOH. Moreover, a relatively small solid-solid phase transition at 603 K was detected from the temperature dependence of lattice parameter, which was not possible to detect by thermal analysis (DTA/DSC). Different types of DSCs were used to measure the heat capacity of Li2CO3, K2CO3 and the intermediate compound LiKCO3. Finally, the Gibbs energy of the pure carbonates and the binary system was generated according to the literature and our new experimental data in the new PCM database, that can provides a better data accuracy.

Keyword(s): Energy (1st)

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Contributing Institute(s):

1. Werkstoffstruktur und -eigenschaften (IEK-2)

Research Program(s):

1. 1243 - Thermal Energy Storage (POF4-124) (POF4-124)
2. PCM-Screening: Evaluierung eutektischer Gemische f. d. Einsatz als PCM: thermodynamische Modellierung und experimentelle Methoden. Teilvorhaben: Thermochemie wasserfreier Salzsysteme für PCM (03ET1441D) (03ET1441D)

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