An NETL-supported project at West Virginia University (WVU) to extract economically and strategically important rare earth elements (REEs) from Appalachian coal resources reached new milestones, such as partial automation of the recovery process, and exceeded its original REE purity and recovery goals. Researchers at WVU’s Water Research Institute used the on-campus Rare Earth Extraction Facility (REEF), which was designed, constructed and commissioned in 2018 as a part of this cooperative agreement, to demonstrate that acid mine drainage (AMD) precipitates from mining sites could be transformed into valuable revenue streams for local communities and businesses using the method of acid leaching solvent extraction (ALSX). “The research conducted at WVU continues to be a source of encouragement,” said Jessica Mullen, NETL federal project manager. “While there is still more work to be done, these researchers have demonstrated that Appalachia can be an attractive source of domestic REE production. If optimized, we may one day see AMD as an opportunity for economic growth instead of just a waste product, all while cleaning up the environment in the process.”

The U.S. Department of Energy’s (DOE) Office of Fossil Energy (FE) has issued a request for information (RFI) to develop technologies needed to attain an uninterruptable domestic supply of critical minerals (CMs) and rare earth elements (REEs). A sustainable domestic supply of CMs and REEs is a U.S. priority because they are used to manufacture cell phones, LED screens, solar panels, energy infrastructure, defense technologies and in other essential high-tech applications. Advances in CM and REE sustainability will improve U.S. ability to overcome supply disruptions, restrictions or embargos of certain CMs and REEs by re-establishing the nation’s once world-leading CM and REE supply chains. Since 2014, DOE/FE and NETL have undertaken research focused on extraction, separation, recovery and purification of CMs and REEs from coal-based materials. This RFI seeks responses on a broad range of applicable CM and REE technologies that extend research beyond what is currently sponsored by DOE/FE and managed by the National Energy Technology Laboratory (NETL). Specifically, DOE/FE is interested in gathering information relevant to four topic areas:

NETL-supported research at Virginia Tech has been recognized by the American Energy Society (AES) as one of the top energy and technology developments of the year for its game-changing economic potential to supply the United States with a steady domestic source of vitally important rare earth elements (REE). The project, titled “Development of a Cost-Effective Extraction Process for the Recovery of Heavy and Critical Rare Earth Elements from the Clays and Shales Associated with Coal,” was chosen by AES as one of the energy technologies of the year in its 2020 Energy Awards. Judges found the project was one of the three “most interesting energy-tech developments of 2020,” with respect to the projected fastest-to-market and long-term impact. AES recognized Virginia Tech’s research as a step forward in developing a domestic supply chain of rare earth elements, which are vital to the manufacturing of personal electronics, energy infrastructure and defense technologies, among many other high-tech applications.

Today, the U.S. Department of Energy (DOE) and NETL announced plans to make available $122 million in federal funding for cost-shared research and development under the funding opportunity announcement (FOA) Carbon Ore, Rare Earth, and Critical Minerals (CORE-CM) Initiative for U.S. Basins. “The Trump Administration is committed to developing technological solutions to extract rare earth elements, critical minerals, and other valuable products from our Nation’s abundant coal reserves,” said Secretary of Energy Dan Brouillette. “These projects have an important role; they will help develop a viable domestic supply of these resources while creating new market opportunities for coal.” This funding is a part of the CORE-CM Initiative, which is sponsored by DOE’s Office of Fossil Energy. This initiative for U.S. basins is intended to catalyze regional economic growth and job creation by realizing the full value of natural resources, including coal, across basins throughout the Nation.

With support from NETL, researchers from the University of North Dakota (UND) and Pacific Northwest National Laboratory (PNNL) identified unique pathways and pretreatments to extract rare earth elements (REEs) from low-rank coal (LRC) ash in a more economical and environmentally sustainable manner that can be adjusted to meet variable conditions. LRCs, such as lignites, are one of the most abundant fossil fuel sources in the world.  NETL-supported project with UND and PNNL researchers has shown that the ash from LRCs can be a potentially viable source of REEs. The research team conducted an extensive characterization effort to understand the form, associations and partitioning of the REEs along with other relevant elements and minerals in the fly ash samples, as well as the ash chemistry, mineralogy and morphology. Understanding these intricacies was a vital step in developing the method for extraction and recovery of the contained LCR REEs.

The United States Energy Association recently hosted a webinar to provide an update on critical minerals (CMs) and rare earth elements (REE) research development and deployment (RD&D) being performed by the U.S. Department of Energy’s (DOE) Office of Fossil Energy (FE), including NETL’s robust in-house research project portfolio as well as the Lab’s extramural program portfolio. The webinar featured opening remarks by Principal Deputy Assistant Secretary for Fossil Energy Kenneth Humphreys and Traci Rodosta, program manager for FE’s Critical Minerals and Coals to Products program. Additional speakers included REE and CM experts from NETL, who were joined by those from industry and academia.

In his long career at NETL, McMahan Gray has experienced more than a few successes. For example, the award-winning research chemist has made valuable contributions to remove carbon from industrial emissions and extract rare earth elements (REEs) from coal byproducts, wastewater and even acid mine drainage. Another ground-breaking contribution may be just around the corner. As part of an ongoing research effort, Gray serves on an NETL team that’s writing a new chapter in the long productive history of coal that may revolutionize how the mineral is used in the future. The team has found that rather than combust coal to produce energy, it can be used in new ways to fuel a transformation in carbon-based, high-tech manufacturing to produce safer cars, faster computers, stronger homes, bridges and highways, and even life-saving biosensors to confirm the presence of disease in the human body.

In an NETL-supported project with Virginia Tech, researchers developed a safe and  efficient processing technology that can extract and concentrate rare earth elements (REE) from coal refuse material already found throughout the Appalachian region, namely in shales and clays. The new process opens the door to future commercialization, as it decreases the size and cost of needed systems. The technologies involved in this process leveraged simple ion-exchange leaching techniques currently used by industry. The Virginia Tech team focused on modified leaching lixiviants, a novel liquid material, instead of acids commonly used to concentrate and extract REEs. Lixiviants are liquid media used in hydrometallurgy to selectively extract the desired metal from the ore or mineral. It assists in rapid and complete leaching, in this case extracting valuable REEs from coal refuse.

With the completion of a recent field test at Pittsburgh Botanic Garden, NETL researchers demonstrated that the Lab’s basic immobilized amine sorbent (BIAS) process could successfully extract rare earth elements (REEs) from acid mine drainage, potentially providing a reliable domestic supply of critical materials needed to produce wind turbines, electric and hybrid electric vehicles, computer components, medical devices, smart phones and other valuable products. Located near Settlers Cabin Park about 10 miles west of downtown Pittsburgh, the Garden was developed on land that was once actively mined for coal and is the site of ongoing efforts to treat acidic water that drains from abandoned mining operations. NETL’s work to remove REEs from mine drainage is rooted in the development of sorbents to capture carbon dioxide (CO2) from coal-burning power plants.

Mary Anne Alvin, an NETL Technology Manager who has earned multiple awards and holds numerous scientific patents, will serve as co-editor of a new book on rare earth elements (REEs) that’s expected to provide the first comprehensive review of the technologies used to extract and process REEs for the manufacturing of high-tech products. “Rare Earth Industry Status and Prospects” is scheduled for publication release by Springer Publishing Company in May or June 2021. It will encompass the international scientific community’s expertise across the entire REE value chain — from field deposits through conventional and the latest state-of-the-art extraction, separation and processing methodologies, alloying, critical market sectors, REE application needs, and much more.  “The development of a reliable and abundant domestic supply of REEs is a priority for our nation. Being able to participate in the editing of a comprehensive, overarching book on rare earths is not only timely, it’s something that hasn’t been done to date, which positions this work as a potentially groundbreaking project,” Alvin said.