Civilization as we know it wouldnโ€™t exist without rare earth elements. No smartphones, LEDs, wind turbines, or even car batteries. REEs, such as cerium and scandium, are scattered throughout the earthโ€™s crust. China alone produces nearly 90ย ยญpercent of the worldโ€™s supply, and the U.S.โ€™s only mine closed this year. But researchers could help break that monopoly with something we already have in ยญabundance: coal and its byproducts.

โ€œEverything thatโ€™s in the earthโ€™s crust is also present within the coal,โ€ explains Evan Granite, a chemical engineer at the U.S. Department of Energy. The DOE recently funded a wave of research to boost U.S. REE production to cope with demand, which is rising about 5 percent every year. Each step of coal productionโ€”mining, cleaning, and burningโ€”creates REE-enriched material. The goal is to use that waste, now sitting in landfills and storage ponds, in a way thatโ€™s cheap and environmentally friendly.

U.S. coal-fired power plants, for example, produce 130 million tons of coal ash each year. A ยญrecent study from Duke University identified billions of dollars worth of REEs within coal burned from coal mined in the Appalachian Mountains and Wyomingโ€™s Powder River Basin. The challenge now is extracting the metals, says Sarma Pisupati, a professor of energy and mineral engineering at ยญPennsylvania State University. His research focuses on rinsing raw shale with an ยญammonium-sulfate solvent to collect REEs early in the coal-production process.

Within a few years, DOE-funded projects will enter pilot testing at U.S. ยญcoal-processing facilities. Perhaps locally sourced smartphones wonโ€™t be far behind.



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