Extracting lithium from hard rock has long demanded brute force: conventional processing of spodumene, the most common lithium-bearing mineral, requires baking the ore at temperatures above 1,000 degrees Celsius before acid treatment. A team including MIT's Yet-Ming Chiang, with co-authors Camden Hunt, Benjamin Mowbray, Kalyn Fuelling, Jacqueline Prawira and Khashayar Jafari, has published in Science a gentler alternative that dissolves the rock in a mixture of water and ammonium fluoride at room temperature.
The chemistry is notable for what it leaves behind, which is very little. The process yields lithium salts alongside smelter-grade alumina and cement-ready silica, turning would-be tailings into saleable co-products, and the reagents are recovered and reused so that waste approaches zero. The team demonstrated the method on 17 spodumene sources from around the world, and estimates the closed-loop route costs about half as much as traditional hard-rock extraction, potentially competitive with brine operations.
The strategic context sharpens the result: lithium demand is climbing steeply with electrification, and refining capacity is heavily concentrated in China. A low-cost, low-waste pathway could allow countries with large hard-rock reserves, including the United States and Australia, to mine and process lithium domestically rather than exporting ore. The technology is now being commercialised through the MIT spinout company Rock Zero.