Turning waste into wealth: Mizzou researchers target Missouri mines for critical materials

Dec. 16, 2025
Contact: Janese Heavin, [email protected]
Photos by Abbie Lankitus

University of Missouri researchers are developing a process to transform abandoned mining waste into an untapped treasure chest of rare earth elements.

Baolin Deng, Curators' Distinguished Professor of Civil and Environmental Engineering and co-director of the Missouri Water Center, and Pan Ni, a research scientist with the center, have secured a $2.8 million grant from the Department of Energy for the work. Other collaborators include Mizzou College of Engineering faculty Jian Lin, Jaewon Lee and Caixia "Ellen" Wan, as well as Quasar Energy Group and the University of Colorado.

Rare earth elements, also known as critical materials, are the magnetic, fluorescent and catalytic powerhouses behind technologies such as electronics, vehicles, national defense systems and more. While not geologically rare, their dispersed nature makes them expensive and difficult to extract. That's one reason the U.S. currently relies heavily on foreign imports of critical materials.

Deng and his team want to change that by extracting rare elements from existing waste found in retention ponds and nearby wastewater at old mining sites across the state.

"If Missouri were to become a leading supplier of these elements, it would be a game changer," Deng said. "It could place the state at the center of the nation's technological future."

Precision engineering

Unlike other methods that take a "catch-all" approach to extracting rare earth elements, Deng's team is crafting technology that targets individual elements at the molecular level.

"There are plenty of materials that can strip contaminants from wastewater, but the key here is selectivity," Deng said. "With 17 rare earth elements that share strikingly similar properties, the ability to separate them individually is transformative."

Their cutting-edge solution: ion-imprinted polymers made from byproducts that come from seafood processing. These special materials are molded to latch onto specific rare earth elements when placed into mining wastewater. They grab the specific elements and filter out everything else.

To elevate the process further, the team is deploying artificial intelligence to continuously improve polymer performance and sharpen element-specific targeting.

"These elements are like twin brothers when it comes to telling them apart," Ni said. "Maybe one weighs just a little more than the other. It's incredibly challenging to differentiate them, but Professor Deng and our research team have proven it's possible. Now, AI will further enhance the selectivity of our material."

The team will spend the first part of the project perfecting polymer precision while also evaluating which waste streams and other sources contain the most valuable concentrations of elements. They will begin field testing at Missouri mining sites in the next few years.

The technology not only unlocks a domestic supply of critical materials, but it also turns environmental liabilities into economic opportunities, making cleanup of old mining sites profitable.

"In the past, cleanup was only a significant cost," Deng said. "By pairing waste management with valuable material extraction, we can make remediation economically viable."

The potential of the research doesn't end at state borders. Mizzou's collaboration with the University of Colorado allows researchers to apply the approach to mineral-rich natural runoff from the Rocky Mountains, further demonstrating national scalability and impact.

"The team is eager to advance this into a truly deployable technology that strengthens the U.S. supply chain," Deng said. "As researchers, we're laying the foundation. Ultimately, we'll want to work with industry to scale it into full-production reality."

MU College of Engineering