Reduction mechanisms and behaviour of zinc ferrite

Abstract

The reduction of dense zinc ferrite (ZnFe₂O₄) in CO-CO₂ and CO-N₂ gas mixtures has been investigated at temperatures between 800 and 1100°C. The rate measurements obtained in these studies were complemented by microstructural characterization of the reacted and partially reduced samples. The reduction kinetics of ZnFe₂O₄ were found to be directly related to the morphology of the reaction product; iron, wüstite and magnetite phases were observed. The various microstructural features of the reaction interfaces and product morphologies were explained in terms of the relative rates of the gas-solid reactions and the mass-transport processes. Changes in growth mechanisms and reduction kinetics that occur with changing reduction conditions are discussed along with the mechanisms of formation of various types of product microstructures.

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Reduction mechanisms and behaviour of zinc ferrite—Part 1: pure ZnFe 2 O 4

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