A non-consumable argon plasma anode for carbon-free electrochemical ironmaking

Abstract

Blast furnace ironmaking produces abundant CO₂, and molten oxide electrolysis (MOE) attracts great interest in ironmaking due to its carbon-free emissions. However, the anodes are the key limiting factor, making them very challenging due to high temperature and the intensive oxidation atmosphere. In this respect, a non-consumable argon plasma anode for iron electrolysis is proposed as a new technological process. During electrolysis, argon ionizes anodically and forms Ar⁺, which will jet into the molten oxide electrolyte and react with the O^2– complex anion from the electrolyte. Metallic iron is obtained by cathodic reduction, while oxygen evolution and argon regeneration occur in the electrolyte through 2O^2–_(complex) + 4Ar⁺ = O₂ + 4Ar, demonstrating the workability of the argon plasma as a non-consumable anode for molten oxide electrolysis.