Coal waste could power U.S. rare earth supply

February 11, 2026

Discarded coal mining materials could soon play a major role in strengthening America’s supply of rare earth elements, as researchers work to reduce reliance on overseas sources essential to clean energy, consumer electronics, and national security.

Scientists at the South Dakota School of Mines and Technology have created an innovative technique to recover valuable rare earth minerals from coal mine waste, including overburden rock and coal ash that are usually abandoned or stored for decades.

After more than three years of development, the research team believes their process could transform mining byproducts into a reliable domestic resource while helping address long-standing environmental concerns.

The project is led by Dr. Venkataramana Gadhamshetty, professor of civil and environmental engineering, and Dr. Purushotham Tukkaraja, professor of mining engineering and management. Their findings are scheduled to be presented to government officials and academic specialists on February 11.

Federal support fuels innovation

The research initiative began with funding from the National Science Foundation and later expanded through the 2DBEST Center. Additional support has been provided by the Office of Surface Mining Reclamation and Enforcement and the U.S. Department of the Interior.

The team concentrated its efforts on coal mining sites in Wyoming, analyzing discarded materials to extract critical rare earth elements such as yttrium, dysprosium, erbium, ytterbium, and gadolinium.

These minerals are essential components in electric vehicles, wind turbines, smartphones, medical imaging equipment, fiber-optic networks, and advanced defense systems.

Advanced three-stage extraction method

To recover rare earth elements efficiently, the researchers developed a three-step extraction system that integrates mechanical, chemical, and biological processes.

In the first phase, large rock fragments are crushed to expose mineral deposits. The second stage uses environmentally responsible chemical solutions to dissolve rare earth elements, allowing precise separation from other materials.

The final step employs specialized microorganisms that absorb the dissolved minerals and store them within their cells, effectively concentrating valuable elements from diluted sources.

Researchers compare this biological process to how the human body absorbs nutrients. By adjusting environmental conditions, scientists can enhance the microbes’ ability to capture rare earth elements.

High-value materials for high-tech industries

Among the extracted minerals, dysprosium, erbium, and ytterbium are especially valuable due to limited global supply and growing industrial demand. Yttrium and gadolinium also play vital roles in electronics manufacturing, LED lighting, and medical technology.

According to the research team, the primary objective was to refine the extraction technology and gain a deeper understanding of the recovery process.

Expanding beyond solid waste

In addition to solid mining debris, the researchers are applying their method to coal mine wastewater, recovering rare earth elements from polluted water sources.

This approach builds upon traditional mineral processing techniques while incorporating advanced chemical and biological methods to improve sustainability and efficiency.

The next phase of development focuses on scaling the technology for commercial use. By improving cost efficiency and performance metrics, the team hopes to attract industry partners interested in large-scale deployment.

Turning environmental challenges into economic opportunities

The project demonstrates how collaboration across engineering, environmental science, and biotechnology can unlock new value from industrial waste.

By converting coal mine residues into strategic resources, the researchers aim to strengthen domestic supply chains, reduce environmental risks, and support emerging clean-energy industries.

This interdisciplinary effort highlights how innovative research can transform environmental liabilities into long-term economic and national security assets.