New tech to make eco-mining a reality for rare earths

They’re the driving force behind electric vehicles and crucial to the manufacture of many high-tech products, but while rare earth elements are highly valued across many sectors, they’re extremely hazardous to extract, posing significant issues for the environment.

Now, new research from the University of South Australia could transform the way rare earth elements and other vital battery metals are recovered from the earth, enabling safer extraction with fewer environmental impacts.

Dr Richmond Asamoah from UniSA’s Future Industry Institute is developing new ways to safely extract critical minerals from downstream ore processing, tailings reprocessing and wastewater treatments. He is also developing mechanisms to safely recycle spent products from scrap batteries and magnets.

“Rare earth minerals and battery metals are vital for the economic wellbeing of the world’s major and emerging economies, yet their supply is not reliable because of geological scarcity, geopolitical issues and trade policy,” he said. “Accumulated mining wastes are becoming an increasingly valuable source of metals and energy, but because there’s a lack of productive and economically viable extraction technologies, there’s also a notable loss of valuable metals.

“The process of extracting these critical materials is very damaging to the environment, with conventional mining methods generating large volumes of toxic and radioactive materials. Our research will identify new technologies that have the capability to both extract minerals from existing industrial wastes and mineral tailings, and recycle and source minerals and metals from spent batteries and magnets.

“As a result, we should be able to significantly reduce the amount of waste and harmful materials that can seep into the environment.”

The project will test two metal recovery processes — resin in pulp and resin in moist mix — to extract target metals from low-grade ores, fine minerals and wastes such as tailings. These processes can also be used to remove harmful substances from water and soils to minimise their environmental impact.

Funded by the Australia-India Strategic Research Fund, Dr Asamoah said that the research will deliver significant benefits to both countries.

“We’re not only talking about environmental benefits, but also economical and sustainable technologies that both countries can use to extract rare earth and battery minerals from current mining operations,” Dr Asamoah said. “Rare earth elements contribute nearly $200 billion to the Indian economy, yet despite India having the world’s fifth-largest reserves of critical metals, they mostly import their rare earth needs from China.

“This project hopes to enable Australia to export rare earth minerals to India, as an alternative to China, as well as to empower India to establish eco-technologies to extract minerals and metals within their own borders. Importantly, the research will build capacity for processing critical minerals in Australia and India and creating many new eco-efficient opportunities for economic growth, employment and investment.”

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