Thermodynamic properties of the BaO-Al2O3 system

Synthesis of the samples in the BaO-Al2O3 system was carried out by solid state synthesis method at the temperature 1250 °C (all samples) and 1500 °C (samples NN 5–10). The characterization of the samples was performed with the use of XRD analysis. The vaporization and thermodynamic properties of BaO-Al2O3 system at 1815 °C from 0.10 to 0.90 Ba mole fractions have been studied by Knudsen effusion differential mass spectrometry.The formation enthalpies from the elements of Ba3Al2O6(s), BaAl2O4(s), BaAl12O19(s) were derived and the recommended values are the following: − 3515 ± 76, − 2338 ± 70 and − 10730 ± 25 kJ/mole respectively. The component activities, Gibbs energies of mixing and excess Gibbs energies were obtained. The thermodynamic properties of the BaO-Al2O3 system at high temperatures are characterized by the negative deviation from the ideal case. •The BaO-Al2O3 system was investigated by Knudsen effusion mass spectrometry.•Partial pressures, components activities, Gibbs energies and excess Gibbs energies.•were determined. Ions current intensities of component species were measured.•The formation enthalpies of solid Ba3Al2O6,BaAl2O4,BaAl12O19 were derived.