Scientists have cost-effectively harvested lithium from seawater
Researchers at King Abdullah University of Science and Technology (KAUST) in Saudi Arabia have figured out how to extract lithium, an essential part of electric vehicle batteries, from seawater in a more cost-effective way.
The study, just published in the journal Energy & Environmental Science and titled “Continuous Electrical Pumping Membrane Process for Seawater Lithium Mining,” states:
The ocean contains about 5,000 times more lithium than on land, but it’s at extremely low concentrations – about 0.2 parts per million. So how do we capture it? Here’s how the KAUST team tackled the challenge using Red Sea water (and an ion is a particle, atom, or molecule with a net electrical charge):
The KAUST team solved this problem with an electrochemical cell containing a ceramic membrane made from lithium lanthanum titanium oxide (LLTO). Its crystal structure contains holes just wide enough to let lithium ions pass through while blocking larger metal ions.
The cell contains three compartments. Seawater flows into a central feed chamber, where positive lithium ions pass through the LLTO membrane into a side compartment that contains a buffer solution and a copper cathode coated with platinum and ruthenium. Meanwhile, negative ions exit the feed chamber through a standard anion exchange membrane, passing into a third compartment containing a sodium chloride solution and a platinum-ruthenium anode.
