The new JV is meant to advance larger-scale development and commercialisation of the process, and a technology package is planned to go on sale from 2024 onwards.

Tech giant Apple helped facilitate the collaboration between Alcoa and Rio Tinto on the carbon-free smelting process, and has agreed to provide technical support to the JV partners.

Executives of Rio Tinto, Alcoa and Apple were joined by Canadian Prime Minister Justin Trudeau and Premier of Québec Philippe Couillard for the announcement.

Trudeau commented: "Today's announcement will create and maintain thousands of jobs for Canadians, significantly reduce Canada's carbon footprint, and further strengthen the aluminium industry in North America. It is a truly historic day for the aluminium industry - and for all Canadian aluminium workers - who play such an important role in our economy and our country's future."

Elysis will be headquartered in Montreal with a research facility in Quebec's Saguenay-Lac-Saint-Jean region. The JV's name refers to the process at the centre of aluminium smelting, the electrolysis of alumina.

Elysis will develop and license the technology, so it can be used to retrofit existing smelters or build new facilities.

"This is a revolutionary smelting process that can deliver a significant reduction in carbon emissions," said Rio Tinto chief executive Jean-Sébastien Jacques.

"It builds on the key role aluminium has to play in driving human progress, by making products infinitely recyclable, stronger, lighter and more fuel efficient. Rio Tinto is proud to work with Alcoa, Apple and the governments of Canada and Quebec, to drive an innovation that can transform the industry and our customers' supply chains."

When fully developed and implemented, it aims to eliminate direct greenhouse gas emissions from the smelting process and strengthen the closely integrated Canada-US aluminium and manufacturing industry. The new JV company will also sell proprietary anode and cathode materials, which will last more than 30 times longer than traditional components.

Canada and Quebec are each investing C$60 million in Elysis. The provincial government of Quebec will have a 3.5% equity stake in the joint venture with the remaining ownership split evenly between Alcoa and Rio Tinto.

Apple is providing an investment of $13 million. The company helped facilitate the collaboration between Alcoa and Rio Tinto on the carbon-free smelting process, and Apple has agreed to provide technical support to the JV partners.

Apple CEO Tim Cook said: "Apple is committed to advancing technologies that are good for the planet and help protect it for generations to come. We are proud to be part of this ambitious new project, and look forward to one day being able to use aluminium produced without direct greenhouse gas emissions in the manufacturing of our products."

Rio Tinto and Alcoa will invest $55 million cash over the next three years and contribute specific intellectual property and patents.

The patent-protected technology, developed by Alcoa, is currently producing metal at the Alcoa Technical Center, near Pittsburgh, US, where the process has been operating at different scales since 2009. The JVintends to invest up to $40 million in the US, which would include funding to support the supply chain for the proprietary anode and cathode materials.

In Canada, the technology could eliminate the equivalent of 6.5 million metric tonnes of greenhouse gas emissions, if fully implemented at existing aluminium smelters in the country. That represents an amount roughly equal to taking nearly 1.8 million light-duty vehicles off the road.

Vincent Christ, an experienced leader with more than 30 years' experience at Rio Tinto Aluminium, has been named chief executive of Elysis. Most recently, he has served as head of technology, research and development and automation programmes. He holds an engineering degree in electronics and industrial information technology.