Approximate Analysis of Metallic Oxide Reduction with Mixtures of Hydrogen and Carbon Monoxide

Abstract

An approximate and simple mathematical model is proposed in order to analyze the reduction behavior of a metallic oxide pellet with gas mixtures of hydrogen and carbon monoxide. The model used is the (single interface) unreacted-core shrinking model, and the following assumptions are made : the gas mixture of hydrogen and carbon monoxide is considered to be as a single-component gas so that oxide pellets are reduced with this imaginary gas, and the apparent reaction rate constant k^a is proportional to the real constant k. The correction factor α(=k^a/k) can be evaluated approximately by the assumption that the reaction rate at the reaction surface is calculated by summing the reduction rates due to hydrogen and carbon monoxide. The evaluated values of α are in a relatively good agreement with the experimental results. These facts show that the simple model proposed can be applied to the reduction processes with mixtures of hydrogen and carbon monoxide.