Engineers extract lithium from extreme environments

Demand for lithium, essential for sustainable technologies to work, is growing rapidly, but up to 75% of the world’s sources of lithium-rich salt water remain unexploitable with current methods.

In the race for solutions to exploit these untapped sources, Monash engineers have developed a world-first technology enabling the direct extraction of lithium from these difficult-to-process sources.

While some predict that global lithium supply could fall short of demand as soon as 2025, the innovative technology – EDTA-assisted free nanofiltration (EALNF) – sets a new standard in lithium processing. The technology extracts lithium and magnesium simultaneously, unlike traditional methods that treat magnesium salts as waste, making it smarter, faster and more sustainable.

The work, co-led by Dr Zhikao Li, from the Monash Suzhou Research Institute and Department of Chemical and Biological Engineering, and Professor Xiwang Zhang from the University of Queensland, promises to meet the growing demand for lithium and opens the path to more sustainable and efficient extraction practices.

Studies undertaken on brines from Longmu Co and Dongtai lakes in China, published today (October 22) in Sustainability of naturedemonstrate how this innovative method could efficiently extract lithium from low-quality brines with high magnesium content.

At the heart of the innovation is a type of nanofiltration that uses a selective chelating agent to separate lithium from other minerals, including magnesium, which is often found in brines and difficult to remove.

“High-altitude salt pans in countries like China (Tibet and Qinghai) and Bolivia are examples of areas with harsher brine conditions that have traditionally been ignored. In isolated desert areas, the large amounts of brine “Water, chemicals and infrastructure needed for conventional extraction are simply not available either, highlighting the need for innovative technologies,” said Dr Li.

“Thanks to Monash University’s EALNF technology, these can now be commercially viable sources of lithium and valuable contributors to the global supply chain. Our technology recovers 90% of lithium, almost double the performance of traditional methods, while significantly reducing the time required for extraction from years to weeks. »

The technology also transforms leftover magnesium into a valuable, high-quality product that can be sold, reducing waste and its impact on the environment.

Beyond its advanced efficiency, the EALNF system provides innovation to address the main environmental concerns related to lithium extraction. Unlike conventional methods that deplete vital water resources in arid regions, this technology produces fresh water as a byproduct.

Dr Li said the system is flexible and ready for large-scale use, meaning it can quickly scale from testing to full industrial operations.

“This advancement is crucial to preventing a future lithium shortage, making it possible to access lithium from hard-to-reach sources and helping to fuel the transition to clean energy.”