It has been released that US researchers have found a way of creating metals like steel in a much cleaner and green way! Their process whilst cutting greenhouse gases, could also produce steel of a higher purity and is said to hopefully be very useful when it comes to space missions.
The new molten oxide electrolysis (MOE) technique uses high temperature electrolysis to make liquid metal and oxygen from a metal oxide feedstock. Although it is limited by it’s high cost and the fact that it only works with consumable or highly expensive and rare anodes like iridium.
Donald Sadoway of the Massachusetts Institute of Technology have discovered that alloy anodes can do the job and over come these limitations. ’For the first time, it shows that earth abundant and affordable metals, and alloys in particular, could be used as an anode in high temperature electrolysis to generate oxygen.’ says Donald.
The team of the institute has observed limited consumption of the anode during the process over a period of five hours and they have said that the stability of the anode is due to the formation of an electronically conductive solid solution of aluminium and chromium oxides in the structure.
Which means a new class of anode material is available to enable scale up, furthermore iron can only be obtained by electrolysis in molten oxide using non-carbon anode. So for steel making in particular this is a deal maker. The removal of carbon in the system allows you to make metal of better quality that is free of carbon impurities.
Existing iron production uses carbon as a reductant and fuel, meaning too much carbon ends up in the iron. Second step, removes the excess carbon to produce mild or low carbon steel with 0.5% carbon.