Coal and Clay: Keys to Unlocking Rare Earth Elements
Amy Plechacek was always a curious child, with a strong desire to learn. Deciding to pursue an education in the sciences seemed like a fitting way to continue that natural curiosity. Initially, she wasn’t sure which career path to follow, however, her love for the outdoors and her appreciation for the protection of Earth’s natural resources led her to embrace geology in her second year of undergraduate studies.
Currently pursuing a master’s degree in environmental chemistry and technology, Plechacek is focusing heavily upon the geochemistry of Wisconsin’s groundwater.
After hearing about a research opportunity from her undergraduate research advisor at Virginia Tech, and seeking hands-on experience in a national laboratory, Plechacek applied and was accepted to the Mickey Leland Energy Fellowship Program (MLEF). The MLEF program provides students with fellowship opportunities to gain hands-on research experience with the Department of Energy (DOE) Office of Fossil Energy. The program’s mission is to strengthen and increase the pipeline of diverse future science, engineering, technology, and mathematics (STEM) professionals.
Plechacek’s fellowship opportunity took place at the National Energy Technology Laboratory (NETL) in Albany, Oregon, where she collaborated with other researchers to analyze coal and underclays, which are clay-rich bands often underlying coal seams, as viable sources for the future extraction of rare earth elements (REE). REE consist of the lanthanide series of elements, and exist in rock deposits in three forms: mineral, colloid and exchangeable. It is vital to understand what form the REE are in so that the appropriate extraction techniques can be implemented.
With her mentor, Circe Verba PhD, Plechacek specialized in the mineral form of REE, and sought to quantify their amounts using both 2-D and 3-D analysis techniques. For the 2-D research, Plechacek used a scanning electron microscope (SEM) to obtain compositional and mineral information from the coal and underclay samples. In the 3-D analysis, data gathered from a focused ion beam-scanning electron microscope was processed in digital rock-analysis software. From a combination of these two methods, Plechacek was able to discern which minerals were present in the coal and underclay deposits as well as the petro-physical properties of the deposits, such as porosity.
The greater goal of the conducted research was to characterize coal and underclay as sources of rare earth elements and provide information that is helpful in developing proper extraction techniques. REE are used in numerous technological and energy-based applications due to their unique properties. Traditional ore-based extraction of these elements, however, is often difficult and expensive.
According to Plechacek, “If production of REE from these deposits is successful, it will assist the U.S. with energy independence and national security.”
During her fellowship, Plechacek learned how to administer new instruments, such as SEM and rock-analysis software, which she says will be invaluable tools for her future as a researcher. Additionally, she gained experience in communicating scientifically, in particular through graphics. Most important of all, however, Plechacek learned to be patient when conducting a research effort.
“Things don’t always go the way you plan, but that’s one of the beauties of research!” Plechacek commented.
Upon completion of her M.S. degree at the University of Wisconsin-Madison, Plechacek hopes to conduct research at a national laboratory or at the U.S. Geological Survey.
Plechacek recommends the program to others, citing the great opportunity to be immersed in research with a national laboratory and to study alongside some of the nation’s top scientists.
The MLEF Program is administered by the Oak Ridge Institute for Science and Education (ORISE) for the U.S. Department of Energy. ORISE is managed for DOE by ORAU.