On many coastlines around the world, piles of discarded oyster and mussel shells are a common sight — the leftovers of a global seafood industry that produces millions of tonnes of waste each year. At the same time, hidden in rocky deposits far from the coast, a very different sort of resource — rare earth elements — is plentiful. These metals are in soaring demand as they are essential for technologies such as wind turbines, electric vehicles, and most modern electronics.
My team’s new research explores an interesting connection between this waste and the critically needed rare earth elements. We found that common seashells, particularly oyster shells, can capture and trap rare earth elements from water. In doing so, the seashells transform from waste into a potential tool for cleaning up pollution linked to the green energy transition.
People in Japan often describe rare earth elements as the “vitamins of modern industry” because, like vitamins in the body, they are essential for many modern technologies but only small amounts are needed. Extracting and processing rare earth minerals them can generate contaminated wastewater, where these elements may leak into the environment.
