GM to extract lithium from toxic sludge

General Motors (GM) and American company Controlled Therman Resources (CTR) have agreed to extract Lithium from superheated waters beneath the Salton Sea in the Southern California desert. 

GM will use the lithium in electric vehicle battery production, starting probably from 2024.

The Salton Sea is an inland water pocket that has been formed and dried up naturally and by man-made mistake several times over millennia, report US news sources.

It was part of the Sea of Cortez between Baja California and mainland Mexico  millions of years ago, but as sea levels fell, the Salton Sea dried up.

More than 100 years ago, people wanting to irrigate crops in the Imperial Valley diverted water from the Colorado River and the Salton Sea filled up again.

Since then, toxic runoff from farmland to the south turned the sea from a resort with “bass, catfish and stripers” into a chemical sludge filled with lithium.

In the newly-announced venture, CTR will pump hot, salty water from deep below the Salton Sea and extract the lithium from it, along with clean thermo energy at the same time. Cleaner water goes back into the Salton Sea and the ground beneath it.

California’s Energy Commission estimates the Salton Sea area could produce 600,000 tons of lithium a year. That’s a huge amount given world’s industry produced 85,000 tonnes of lithium in all of 2019. 

“CTR’s lithium resource at the Salton Sea is one of the largest known lithium brine resources in North America,” CTR says in a statement.

“The integration of direct lithium extraction with renewable geothermal energy offers the highest sustainability credentials available today.

“CTR’s closed-loop, direct lithium extraction process utilises renewable power and steam, significantly reducing the time to produce battery-grade lithium products and eliminating the need for overseas processing.”

GM executive Doug Parks says lithium is critical to battery production and will become more important as consumers adopt EVs.

“By securing and localising the lithium supply chain in the US, we’re helping ensure our ability to make powerful, affordable, high mileage EVs while also helping to mitigate environmental impact and bring more low-cost lithium to the market as a whole.”

CTR says it should start delivering lithium to GM by 2024.