Sustainable iron production via highly efficient low-temperature electrolysis of 3D conductive colloidal electrodes†
Abstract
Towards decarbonizing the carbothermic reduction of iron and steelmaking, which produces around 5% of global CO2 emissions, we herein propose a low-temperature electrolysis (100 °C) with 3D electrically–ionically conductive colloidal Fe2O3 electrodes as a novel and sustainable alternative. With the designed electrodes that offer a 3D conductive network to facilitate the electrochemical reduction of Fe2O3 at such a low temperature, high-purity Fe powder (>95%) can be produced with high current efficiency (>95%) and no direct CO2 emission. In addition to Fe, we also demonstrate the production of metal and alloy powders such as Cu, Ag, and an FeNi alloy using the proposed method. A techno-economic assessment of the process is performed to evaluate industrial feasibility as well as CO2 emission analysis. Altogether, this alternative process is green, environmentally friendly, and energy efficient, showing great potential for revolutionizing the conventional process that has had a significant environmental impact for decades.