The demand for lithium is skyrocketing because it’s a key ingredient in batteries for mobile devices, electric cars, and clean energy storage.
But mining lithium is expensive, slow, and harmful to the environment.
Now, scientists at Imperial College London have developed a new membrane technology that can efficiently extract lithium from saltwater sources like salt-lake brines and geothermal waters.
A cleaner, faster way to extract lithium
Currently, extracting lithium from brine takes months and requires large amounts of water and chemicals, which harms the environment and produces greenhouse gas emissions.
However, Dr. Qilei Song and his research team have created a special membrane that can filter lithium from saltwater quickly and efficiently.
The membrane works by separating lithium ions from other elements like magnesium, which is often a problem in traditional filtration methods.
Their breakthrough material, made from polymers of intrinsic microporosity (PIMs), contains tiny, hourglass-shaped pores that act as highly selective filters, allowing only lithium to pass through.
The membrane is used in a process called electrodialysis, where an electric current pulls lithium ions through the membrane, leaving behind larger and unwanted ions like magnesium.
When tested in a lab using simulated salt-lake brines, the new membrane successfully extracted high-purity lithium, suitable for battery production.
One major advantage of this method is that these membranes can be made on a large scale using existing industrial techniques. The polymers used are soluble in common solvents and can be easily integrated into commercial filtration systems.
Imperial College has already filed patents for these membranes and is working on bringing this technology to the market. Dr. Song and his team are setting up a climate tech company to partner with industries for large-scale lithium extraction using real saltwater sources.
“We are excited to work with companies to extract lithium efficiently and sustainably,” Dr. Song said.
This membrane technology could do more than just extract lithium. Professor Sandro Macchietto, Director of Enterprise at the Department of Chemical Engineering, believes it has huge potential for water purification, energy storage, and recycling valuable materials in a circular economy.
Researchers are also exploring ways to use this membrane to extract copper and other metals from mining waste, making the process more sustainable.
By offering a faster, cleaner, and scalable way to harvest lithium, this breakthrough could play a major role in powering the future of clean energy while reducing the environmental impact of mining.
