Critical Minerals and REEs in Coal And Coal Wastes: Extraction and Environmental Perspectives

Research studies have demonstrated the technical feasibility of extracting high-purity critical minerals and separating high-purity REEs from low concentrates in coal and coal wastes. The low concentrations of REEs require extremely high volumes of coal/coal wastes for economic recovery. Extraction studies through bench-scale experiments rely on chemically intensive processes with the potential production of huge volumes of extraction wastes in future large-scale economic commercialization. Attempts to reduce the use of chemicals such as acid leaching for separation of REEs from REE-bearing coal wastes have been demonstrated in pilot-scale projects funded by the United States Department of Energy authorized by the 2020 Energy Act. These applied research projects are enabled to demonstrate environmentally sustainable pathways to reduce cost of commercial-scale production of high-purity REEs, which they have accomplished to an acceptable degree. The push for large-scale production and commercialization of REEs is strongly motivated by protection of national security and indispensable applications to advanced technologies like computer hard disks and monitors, smartphones, digital cameras, flat screen televisions, magnets in wind turbines, etc. Thus, this government-funded applied, scientific, and technical research deserves recognition as they drive innovation, solve real-world problems, and improve society