Abstract:
The Hall–Héroult process for the production of aluminium uses a consumable carbon anode. Owing to the environmental effects of the consumable carbon anodes, the primary aluminium industry is under increasing pressure to improve on the Hall–Héroult process to make it more environmentally friendly. Inert anodes would provide a major technical revolution, as they may yield significant cost, energy and environmental benefits. However, no fully acceptable inert anode material has been developed to date. Other alternative technologies had been investigated and tested, but with little success so far. The use of a hydrogen anode for the production of aluminium is an interesting concept, as it will have the same reversible voltage as a carbon anode in a conventional Hall–Héroult cell, and it will considerably reduce greenhouse gas emissions. This paper reviews the various process options for aluminium electrowinning with a focus on the application of hydrogen anode in aluminium electrowinning.