Production of iron and oxygen in molten K 2CO 3–Na 2CO 3 by electrochemically splitting Fe 2O 3 using a cost affordable inert anode

Abstract

Iron oxide was electrochemically split into iron and oxygen gas in molten Na 2CO 3–K 2CO 3 at 750 °C using a solid iron oxide cathode and a Ni10Cu11Fe alloy inert anode. Fe 2O 3 was electrochemically reduced to Fe on the cathode, releasing oxygen anions into the electrolyte and which were oxidized on the anode to generate O 2. The cathodic current efficiency was as high as 95% and the energy consumption for producing 1 kg iron was 2.87 kWh, only half of the current industrial energy consumption of blast-furnace steel production. Due to the cost-affordable inert anode and the high energy efficiency, the method demonstrated in this work shows promise as a practical “green” iron production process.