A.C. Impedance Analysis of the Kinetics of Reactions between Molten Cu or Fe and CaO-Al₂O₃ Slag

Abstract

A chemical reaction at the interface between slag and metal can be analyzed as a kind of electrode reaction because of the ionic nature of liquid slag.
In the present work, application of an A.C. impedance method to slag-metal reaction in iron- and steel-making process was tried to clarify the individual kinetic factors concerning the electrode reactions at the interface between slag and metal. The total impedance between CaO-Al₂O₃ slag and Cu-S or Fe-C-S melts was measured in this paper.
The results obtained were successfully used to determine the individual factors on kinetics of the electrode reaction between slag and metal, such as solution resistance of slag, interfacial capacitance in electric double-layer, overvoltage of charge transfer, rate constant and so on.