Alcoa and other big aluminum producers have been interested in eliminating the carbon anodes from aluminum smelting for decades, well before global warming conc

Alcoa and other big aluminum producers have been interested in eliminating the carbon anodes from aluminum smelting for decades, well before global warming concerns rose to the forefront. It is a very difficult problem to make inert anodes efficient and stable enough for long term industrial use. I hope that these recent advancements are enough to start replacing carbon anodes in commercial plants. Some of the non-CO2 reasons to eliminate carbon anodes: - Carbon anodes oxidize while they are in use. Their shape and size changes over time as they erode, and the pot has to be shut down to replace ones that are too worn. - The oxidation of carbon anodes contributes part of the energy needed to transform aluminum oxide into metallic aluminum, but their embedded energy content is much more expensive than the electricity smelters use. The combined materials + electricity cost to produce a ton of aluminum would be lower if efficient, stable inert anodes could be developed. - The oxidation of carbon anodes, ideally, produces pure carbon dioxide. But in actual operating conditions the anode oxidation also produces toxic gases like carbonyl fluoride and carbon monoxide as minor byproducts. Safety systems and processes to prevent toxic gas exposure of workers make it more expensive to build and operate smelters than if the byproduct gas were oxygen.