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

Influence of the basicity on the redox equilibrium in the CaO-FeO-Fe₂O₃-SiO₂ system

P. Kurka, J. Kupčák, and J. Leško

Institute of Metallurgical Processes Theory, Czechoslovak Academy of Sciences, CS-70300 Ostrava

Abstract: The redox Fe(III)/Fe(II) ratio in the CaO—FeO—Fe₂O₃-SiO₂  melts in equilibrium with air at the temperatures of 1400 °C, 1500 °C, and 1600 °C was measured. For the dependence of the redox ratio j on the temperature and the composition the following equation was derived j = 1.6736 - 6.922 x 10^-4 T + 0.2927k - 6.181 x 10^-3 x'( Fe₂O₃ ) The activity coefficients γ(FeO) and γ(FeO_1,5) were calculated using the model of the regular solutions. The dependence of the a(FeO_1,5) /a(FeO) activity ratio on the basicity shows a minimum at the ratio x(CaO)/x(Si0₂)≈1. Such course of this dependence is explained by the amphoteric behaviour of the iron(IIl) oxide.

Full paper in Portable Document Format: 435a633.pdf

Chemical Papers 43 (5) 633–641 (1989)