Zethos: Recovering critical minerals efficiently

The world needs far more critical minerals than it produces. Zinc, copper, nickel and manganese go into renewable energy generation and supply, electric vehicles, data centres, security systems, and construction, and demand is set to roughly double within a decade. Conventional refining leans on energy-intensive, high-temperature furnaces and is heavily polluting.

For more than a decade, Professor Aaron Marshall from the University of Canterbury's (UC) Department of Chemical and Process Engineering has been researching new ways to recover valuable minerals from industrial waste while reducing the environmental impacts of conventional refining.

That research led master's student Jonathan Ring to investigate the recovery of zinc and acid from the waste generated by the galvanising industry. Together, their work laid the technical foundation and built the initial team for what became Zincovery, and later Zethos, as the process expanded beyond zinc recovery and moved towards commercial scale.

Today, Zethos’ patented platform uses selective reduction and electrochemistry to separate individual minerals from industrial waste and cast them into ingots ready for sale. The process has halved operating costs, reduced energy use by up to 70%, and reduced carbon emissions by up to 95% compared with conventional refining. 

Founded in 2021, Zethos has since raised over $16 million in capital to scale from initial lab and pilot operations at UC to a demonstration-scale facility in Bromley, Ōtautahi Christchurch. Housed in a new 3,000m² building, the facility is 100 times the size of the UC pilot and is at the last stage of research and development before full commercialisation.

Critical mineral security is now a global concern, with most supply coming from a handful of countries using carbon-heavy processes. Recovering metals from waste that would otherwise go to landfill turns a disposal problem into a domestic supply. The Bromley plant is already Aotearoa New Zealand's only domestic source of high-grade zinc. It points to a more sustainable and secure critical-minerals industry, one built on recovered waste and smarter, cleaner technology.

Talk to Professor Aaron Marshall about the underlying refining technology, industrial electrochemistry, energy technologies, and hydrogen system, or contact the Commercialisation Team to explore licensing, partnership, and investment opportunities in critical minerals and cleantech innovation.