Zero-carbon aluminum in your iPhone

Posted on 05 May 2020.

At the end of 2019, Apple announced its purchase of the first-ever commercial batch of zero-carbon aluminum. Manufactured by Elysis, an Alcoa and Rio Tinto joint venture, it will be used in some of Apple's products.

A revolution that could change the way one of the world's most widely used metals is produced.


Aluminum is one of the most widely used metals in the world. It is also a key material for Apple, since the manufacturer uses aluminum cases in the majority of its electronic devices (iPhone, Mac computers, iPad, etc.). But, like any metallurgical process, aluminum production has a significant environmental impact.

As part of its commitment to reduce its environmental footprint, Apple is seeking to manufacture its products using more sustainable processes and materials. In 2018, for example, the firm announced the release of the MacBook Air made with recycled aluminum. By investing in the development of zero-carbon aluminum, Apple has taken its action to another level.

In a press release in 2018, Apple said it was "instrumental in the creation of a joint venture [between aluminum producers Alcoa and Rio Tinto] that could transform the future of global manufacturing. Apple acted as a catalyst in the development of a new aluminum smelting technology and partnered with the two aluminum producers.

Apple's involvement actually dates back to 2015, when three of its engineers discovered that Alcoa, the world's third-largest aluminum producer, was developing a new production method to eliminate direct greenhouse gas emissions from the smelting process, a key step in the manufacture of aluminum.

 

O2 instead of CO2

  As surprising as it may seem, the process hasn’t changed since it was simultaneously invented at the end of the 19th century by Paul Héroult in France and Charles Martin Hall - the founder of Alcoa - in the United States. It consists of subjecting alumina, extracted from bauxite and introduced into electrolysis tanks with additives, to a powerful electric current in order to trigger a redox reaction. This chemical reaction releases significant amounts of greenhouse gases, such as carbon dioxide.   The new process developed by Alcoa's R&D teams replaces carbon materials with "an advanced conductive material" that, instead of emitting carbon dioxide (CO2), releases oxygen (or oxygen, O2). A revolution that could - at last! - change the way one of the world's most widely used metals is made.

To perfect this smelting technology and enable large-scale production and marketing of zero-carbon aluminum, Alcoa joined forces with Rio Tinto, an Anglo-Australian mining group, to form the joint venture Elysis. By introducing zero-carbon aluminum into its products, Apple demonstrates that it is possible to make our everyday electronic devices differently.
 

CREDIT: Main picture © Getty Images