TPR data regarding the effect of sulfur on the reducibility of α-Fe 2O 3

Abstract

The temperature programmed reduction (TPR) method has been used to study the effect of residual sulfur on the reducibility of α-Fe 2O 3 prepared both using iron(II) and iron(III) sulfate. The values of the kinetic parameters characteristic of the reduction of the hematite to magnetite, of the magnetite to metallic iron, as well as of the processes involved in the elimination of the sulfate anions, were evaluated by simulation of the TPR curves. The effect on the reducibility of α-Fe 2O 3 is reflected in the values of the kinetic parameters when the sulfur is dispersed into the sample's bulk. If the sulfur exists only on the surface, its influence on the reducibility of the sample is mainly due to the fact that the reduction of the hematite starts only after the elimination of the sulfate anions begins.