| Abstract Scope |
Iron and steel production accounts for 7% of global CO2 emissions due to the predominant use of carbothermic blast furnaces. Current carbon-free alternatives, solid-state direct reduction and scrap remelting, are limited in raw materials supply.
Here, we explore the opportunity space of hydrogen plasma reduction, a promising low-carbon technology to supply molten iron separated from gangue. In this approach, FeOx reduction is achieved through energetic species generated in the plasma. Depending on their gas temperature, plasmas are classified as thermal, “warm”, and non-thermal plasmas, and they include electrons, radicals, ions, and excited species, along with radiative energy transfer. Reactive plasma species possess higher reduction enthalpies than ground-state H2 and with reactivities that scale as follows: H+ > H2+ > H3+ > H > H2. While electron-impact processes in the plasma can provide these high energy species, the coupling of gas phase plasma dynamics with plasma-iron-ore interactions remains vastly unexplored. |