A New Ultra-Adsorbent Material Can Suck Up 20 Times More Uranium Than Rival Methods

And seawater holds billions of tons.

Loukia Papadopoulos
A New Ultra-Adsorbent Material Can Suck Up 20 Times More Uranium Than Rival Methods
Grand Bé and seawater pool at sunset, viewed from Saint Malo walls.VFKA/iStock

According to the Nuclear Energy Agency, it’s estimated that there are at least four billion tons of uranium in the oceans, which corresponds to about 500 times the amount of uranium known to exist in land-based ores. But mining and extracting that uranium from the sea has been notoriously hard to execute, until now.

Linsen Yang at the Chinese Academy of Sciences in Beijing and colleagues created a polymer membrane that mimics the way that blood vessels operate and added a material that was impregnated with a compound called amidoxime which binds to uranium ions. In this fashion, they managed to create new material that can absorb 20 times more uranium from seawater than its predecessors.

To detect whether uranium was truly captured, the team used X-ray photoelectron spectroscopy. They further discovered that the uranium-laced material could also be cleaned with hydrochloric acid, removing 98 percent of the uranium. They also found that their solution allowed their material to be used for long periods of time over and over again, significantly reducing the cost of uranium mining.

The scientists said that they were inspired by the geometry of blood vessels. “Here, inspired by the ubiquitous fractal structure in biology that is favorable for mass and fluid transfer, we describe a hierarchical porous membrane based on polymers of intrinsic microporosity that can capture uranium in seawater,” wrote the researchers in their study.

“This biomimetic membrane allows for rapid diffusion of uranium species, leading to a 20-fold higher uranium adsorption capacity in a uranium-spiked water solution (32 ppm) than the membrane with only intrinsic microporosity.”