Strategic Design and Development of a Plant Bio-Mining System to Sustainably Harvest Rare Earth Elements from Domestic U.S. Sources.
Colleen J. Doherty
Project runs from 07/01/2019 to 06/30/2022
Despite their abundance in US soils, REEs are dispersed and challenging to extract. The economic and environmental costs of extraction combined with the low resale value of REEs has resulted in decreased US production of REEs. The lack of US companies with the resources and interest in continuing to harvest REE generates a national security risk as the availability of these essential components is under foreign control. Current methods of REE extraction require the use of aqueous chemical treatments. New advances include the use of bacterial filters to capture REE. While these have contributed to reducing the cost of extraction, these approaches still require significant capital investment and a large amount of water to excavate and recapture the REE. Thus, these are approaches that can only be economically employed in areas with large deposits of REEs.
The successful completion of this proposed research will result in an economical plant bio-mining system to extract REE from soil and waste sources. The low costs and minimal footprint of the plant bio-miners will provide an efficient and scalable approach that can be deployed in areas ranging from small fields and consumer waste areas to large mines and reclamation areas. The low upfront costs will encourage the use of plant bio-miners thus reducing the scarcity of REEs and eliminating our dependence on foreign REE sources. The design and engineering of the plant bio-mining system will provide tools to understand how plants regulate uptake and distribute REEs and calcium, which REEs mimic. Small doses of REE can enhance tolerance to abiotic stress. The development of this system to accumulate REEs in plants will help us design REE-inspired treatments to mimic these positive effects on abiotic stress responses and enhance tolerance to drought and heat stress.