Critical evaluation and thermodynamic modeling of the Al-Mn-O (Al_2O_3-MnO-Mn_2O_3) system

摘要

In the present study, a complete thermodynamic description of the Mn-Al-O (MnO-Mn_2O_3-Al_2O_3) system has been carried out. All the experimental phase diagram data from metal saturation to 1 atm oxygen partial pressure, thermodynamic data for spinel and liquid phases and structural data for spinel were critically evaluated and optimized in order to obtain Gibbs energies of all phases as functions of temperature and composition. The MnAl_2O_4-Mn_3O_4 spinel solution was modeled using the Compound Energy Formalism considering the cation distribution between tetrahedral and octahedral sites. The slag phase was described using the Modified Quasichcmical Model considering both, the Mn~(2+) and Mn~(3+) species.