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Pennsylvania stream impacted by acid mine drainage. Photo Credit: Pennsylvania State University |
Critical minerals, including rare earth elements, are used to power devices like smartphones and computers and are essential to our nation’s economy and national security. Penn State’s Center for Critical Minerals has developed a new purification process that extracts mixed rare earth oxides from acid mine drainage and associated sludges at purities of 88.5%
Critical minerals (CMs), including the 17 rare earth elements (REEs), are used in many common household products like smartphones and computers, and in many commercial products such as electric vehicles, batteries and solar panels. Demand for them has skyrocketed, and they are classified as critical because they have high economic importance, high supply risk, and their absence would have significant consequences on the economic and national security of the United States.
Acid mine drainage (AMD) and associated solids and precipitates resulting from AMD treatment have been found to be viable sources of multiple CMs, including REEs, aluminum, cobalt and manganese.
The U.S. Department of Energy (DOE) has funded efforts to demonstrate both the technical feasibility and economic viability of extracting, separating and recovering REEs and CMs from U.S. coal and coal by-product sources, with the goal of achieving mixed rare earth oxides from coal-based resources with minimum purities of 75%.