Effects of inert anodes in the FFC Cambridge reduction of hematite

Abstract

The industrial production of iron and steel contributes to a significant share of the global CO₂ emissions. Electrochemical methods using an inert oxygen evolving anode can eliminate the CO₂ formation. The FFC Cambridge process approach was tried out for the reduction of hematite to produce iron at 915°C, using hematite pellets made for industrial blast furnaces. The electrolyte consisted of pure molten CaCl₂ containing 0·5 mol.-%CaO. Different anodes were tested. Graphite anodes were found to halt the reduction of the inner parts of the cathode pellets. Also large amounts of carbon were found in the cathode product in these experiments. Nickel ferrite cermet with intergranular nickel and copper was tried as an inert oxygen evolving anode material. These anodes showed promising behaviour and also made the cathode pellet more active with respect to electro reduction. Iron was found to be formed during the process.

Keywords

NICKEL FERRITE CERMETS INERT ANODES GRAPHITE BEHAVIOUR IN CALCIUM CHLORIDE CURRENT EFFICIENCY

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