ANÁLISIS DE LA CONDUCTA IÓNICA DEL SISTEMA HIERRO-OXÍGENO

Abstract

In this work two complementing ionic models are presented. A single anionic and cationic distribution of species results when the FeO-Fe3O4-Fe2O3 system is considered as an ionic melt or as an equilibrium molten salt. The first model was derived from the model based on the analysis of three molecular subsystems, namely FeO-Fe2O3, FeO-Fe3O4, and Fe3O4-Fe2O3. The ionic model for each of the subsystems was found to be ruled by the Temkin principles which led to the prediction of the  quasi ternary behavior of the Fe2+-FeM+-Fe3+ ions. The O2- ions as well as the nonionic species, O2(g) and Fe0, were involved in the model to satisfy the charge balance and stoichiometry. The second model is based on the occurrence of two simultaneous events: the FeO dissociation and the formation of complex species of Fe2O3 under critical molar proportions that lead to the equilibrium between Fe2+ and anionic complexes of the type FenOmi-. The nature of these critical equilibria is analyzed under the light of molar, simple or superimposed ionic distribution when considered as the quasi ternary systems FeO-Fe3O4-Fe2O3 or Fe2+-FeM+-Fe3+.