Lithium is driving the global energy transition, being used in the batteries that power electric cars and in the huge banks used for renewable energy storage. Demand for lithium continues to grow with the battery supply chain (from mining to recycling) being projected to reach a market value of $400 billion and create 18 million new jobs.
Lithium is actually not rare. However, it is highly reactive and rarely found in pure form. Instead, it is thinly dispersed in rocks, soils, and natural waters, making it expensive, time-consuming, and environmentally harmful to extract. Lithium is mostly extracted using solar evaporation whereby the salty brine formed under deserts that contains it is pumped into sprawling ponds that bake for up to two years under the desert sun. The method is only feasible in dry, flat regions with vast amounts of land, such as Chile’s Atacama Desert or parts of Nevada.
Researchers at Columbia University have developed a new technique they call S3E, which stands for switchable solvent selective extraction. It exploits the way lithium ions interact with water molecules in a solvent system that changes its behavior based on temperature. At room temperature, the solvent pulls lithium and water from the brine. When heated, it releases the lithium along with water into a purified stream. It is much faster and environmentally much friendlier than existing lithium extraction techniques.
So far, there has only been a proof-of-concept study but results so far indicate that S3E may offer an alternative to both evaporation ponds and hard-rock mining. The world is demanding more and more lithium, and this may represent a better way to get it.
