MIT team develops room-temperature lithium process from spodumene

Researchers at the Massachusetts Institute of Technology (MIT) have developed a low-temperature, closed-loop process for extracting lithium salts from spodumene ore, with aluminum and silica streams recovered as co-products and projected costs roughly half those of conventional hard-rock extraction.

The process, published in the journal Science, uses a liquid reagent combining water and ammonium fluoride to dissolve spodumene at or near room temperature — contrasting with the more than 1,000 C required by conventional hard-rock extraction. Rather than discarding the remainder of the rock, the method yields lithium, aluminum, and silica streams from the ore.

The researchers evaluated the lithium output against battery-grade specifications, tested the aluminum fraction for suitability as smelter feed, and assessed the silica as a potential cement additive, all at laboratory scale. The solvent and reagent are recovered and reused, with the researchers reporting that waste levels approach zero in the closed loop under laboratory conditions.

The researchers estimate the process costs roughly half as much as conventional hard-rock lithium extraction, which they said could make it cost-competitive with brine-based production. The team tested the chemistry on 17 different spodumene rock sources.

“By 2040, we need to quadruple production of lithium globally, which amounts to hundreds of new lithium producing assets,” said Camden Hunt, a former project manager at MIT’s Center for Electrification and Decarbonization of Industry and a co-author of the paper. “Hard rock is abundant; you can find it everywhere. But most hard rock refining is done in China. Our central thesis is if you can find an easier way to crack the rock, get lithium out, and make battery-grade lithium salts, you can change the lithium market.”

The research team has begun commercializing the technology through Rock Zero, an MIT spinout now based at The Engine, MIT’s nonprofit incubator in Boston, where the process is being scaled from laboratory batches. Commercial viability at battery-industry volume has not yet been demonstrated.

“We believe this approach is the lowest-energy, lowest-cost way of getting lithium not only out of hard rock, but period,” said Yet-Ming Chiang, MIT’s Kyocera Professor of Materials Science and Engineering and a co-author, describing the team’s assessment of the technology’s potential.

The work was supported in part by the US Department of Energy’s Advanced Research Projects Agency-Energy, the MIT Climate Grant Challenges program, and the National Science Foundation.

The MIT process enters a field where several groups are pursuing lower-energy routes to hard-rock lithium. Demand for the metal is expected to rise sharply through 2040 as battery production scales for electric vehicles and grid storage, with conventional spodumene extraction – which requires high-temperature roasting and produces significant waste – increasingly scrutinized for both cost and environmental reasons.