Low-cost- ECO-friendly recovery of rare earth elements (rees) from coal mine wastes through phytominingvirginia polytechnic institute and state universitycoal mine wastes are promising secondary…

The U.S. Department of the Interior's Office of Surface Mining Reclamation and Enforcement (OSMRE) awarded a $200,000 Cooperative Agreement to Virginia Polytechnic Institute & State University (Virginia Tech) under the "Science and Technology Projects Related to Coal Mining and Reclamation" CFDA program. The objective is to develop and verify a novel phytomining-based process that enables simultaneous rare earth element (REE) recovery and solid waste reclamation from coal mine wastes. Key aspects include bench-scale phytomining, hydrothermal processing, and REE extraction and purification to optimize plant growth, determine REE fate, and identify optimal conditions for REE recovery. The goal is to facilitate more sustainable and lower-cost REE production from coal mine wastes. Virginia Tech is collaborating with North Carolina State University on this project as a sub-grantee. The award period runs from February 1, 2024 to January 31, 2026.

Low-cost- ECO-friendly recovery of rare earth elements (rees) from coal mine wastes through phytominingvirginia polytechnic institute and state universitycoal mine wastes are promising secondary resources of rare earth elements (rees). Over the past few years- REE production from coal mine wastes has progressed through feasibility assessment- filed sampling and characterization- bench-scale recovery- and pilot-scale REE production stages. However- REE recovery from coal mine wastes using existing methods reported in the literature generates a large amount of fine- unstable- and chemical-containing solid waste- which will hinder the production at larger scales due to the adverse environmental impact. Unfortunately- this issue has not received enough attention. The objective of this project is to develop and verify a novel phytomining-based process that enables simultaneous REE recovery and solid waste reclamation. In this process- rees are concentrated from coal mine wastes into plants through phytomining- while hydrothermal processing and extractive metallurgy are used to process the REE-rich plants to obtain high-grade REE products and additional valuable products- such as hydro-char and BIO-oil. The new process will facilitate the recovery of rees from coal mine wastes in a more sustainable manner- at low cost and with small carbon footprints. In order to achieve the objective- an interdisciplinary team consisting of experts with different backgrounds has been formed. The team will conduct systematic benchtop phytomining- hydrothermal processing- and REE extraction and purification tests to optimize plant growth- determine the fate of rees during hydrothermal processing- and identify optimum conditions for REE recovery from REE-rich material stream(s) of hydrothermal processing. By combining with techno-economic analysis and life cycle assessment- benchtop test results will be used to optimize the process and verify its sustainability. Several meaningful deliverables are expected from this project- including but limited to a proven phytomining-based process- a technology patent- and a number of peer-reviewed journal publications. The broader impacts of the project are (1) promoting REE production from coal mine wastes with the new process that requires low cost- low carbon emissions- and negligible solid waste management- (2) creating a more friendly living environment for the residents of mining communities by providing long term reclamation benefits- and (3) facilitating the establishment of secure REE supply chains that can support the economic development and social prosperity in the united states.