New technology leads to carbon-free aluminium

Canadian company Elysis, a joint venture of global aluminium industry leaders Alcoa and Rio Tinto, developed a new method to make aluminium that eliminates all direct greenhouse gases and produces oxygen.

Aluminium is a popular metal thanks to its light weight and strength. In addition, once produced, aluminium is infinitely recyclable, as it doesn’t degrade in the process like materials as paper and plastic.

The first industrial large-scale production method for aluminium was developed in 1886 by French engineer Paul Héroult and US engineer Charles Martin Hall. This process is now known as the Hall-Héroult process and greatly increased the world output of aluminium. However, the process produces a lot of greenhouse gasses, amongst them carbon dioxide.

The new patent-protected process by Elysis eliminates all these greenhouse gasses, and instead has oxygen as by-product. The name of the venture refers to the process at the centre of the industry, the electrolysis of alumina.

If the technology were fully implemented in all aluminium smelters in Canada, it would save 6.5 million tonnes of greenhouse gas emissions. This is about the equal of taking 1.8 million cars off the road. The process would produce as much oxygen as a forest of 25,000 square kilometres (10,000 square miles).

In addition, the new technology is said to create more aluminium in the same size smelting cell as the traditional process. It can be installed in new facilities or retrofitted for existing ones.

The technology, not only supported by Alcoa and Rio Tinto, but also the governments of Canada and Québec, and Apple, is planned for sale in 2024.

Image: Elysis