ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Thermodynamic Analysis of Pseudobinary Subsystems of the System CaO—TiO₂—SiO₂

I. Nerád and V. Daněk

Institute of Inorganic Chemistry, Slovak Academy of Sciences, SK-842 36 Bratislava

E-mail: uachnera@savba.sk

Received: 18 December 2000  Accepted: 17 January 2002

Abstract: The thermodynamic model taking into account the structural behaviour of TiO₂ in silicate melts was applied to describe the activities of the components in the melts and to calculate the phase diagrams of the systems CaSiO₃—CaTiSiO₅, CaSiO₃—CaTiO₃, Ca₂SiO₄—CaTiO₃, CaTiSiO₅— CaTiO₃, and CaTiSiO₅—TiO₂. When the present TiO₂ is assumed to be completely integrated in the structural network in the form of tetrahedrally coordinated units, i.e. it acts as network former, the considered thermodynamic model fits quite well both experimental liquidus curves in the systems CaSiO₃—CaTiSiO₅ and CaTiSiO₅—CaTiO₃ and the CaTiSiO₅ liquidus curve in the system CaTiSiO₅—TiO₂. The model fails in the systems Ca₂SiO₄—CaTiO₃ and CaSiO₃—CaTiO₃ as well as by the TiO₂ liquidus curve in the system CaTiSiO₅—TiO₂. For both liquidus curves in the system Ca₂SiO₄—CaTiO₃ and for the TiO₂ liquidus curve in the system CaTiSiO₅—TiO₂ better fit of the experimental liquidus curves was achieved when activities were equal to mole fractions.

Full paper in Portable Document Format: 562a77.pdf

Chemical Papers 56 (2) 77–83 (2002)