Demand for lithium has surged in recent years as lithium-ion batteries power increasingly more of our world. And yet, even as places like the U.S., Europe, and Australia have abundant lithium resources within their borders, China dominates global lithium refining. The biggest hurdle to tapping into the U.S. and Australia’s lithium is getting it out of hard rock minerals in a form that is useful.
Extracting lithium from hard rock today is an energy- and waste-intensive process that is often far more expensive than getting lithium from brine water, which also has major environmental drawbacks. Currently, lithium hard rock extraction involves baking the rock at over 1,000 Celsius and chemically leaching it to extract lithium. The rest of the rock is discarded.
Now, a team of researchers from MIT and elsewhere has developed a low-temperature process for extracting battery-grade lithium from the most common type of lithium-bearing mineral. The process uses a liquid reagent to dissolve the rock into the useful forms of its constituent parts: not just battery-ready lithium salts, but also smelter-grade alumina and cement-ready silica. After the minerals are extracted, the solvent and reagent can be recovered and used again so waste levels approach zero.
