The LLNL-led team will use microorganisms to separate and purify rare earth elements; biomining

Using natural and engineered proteins and bacteria, Lawrence Livermore National Laboratory (LLNL) scientists and collaborators will separate and purify rare earth elements for use in the defense sector.

Under the Defense Advanced Research Projects Agency’s (DARPA) Environmental Microbes as a BioEngineering Resource (EMBER) program, the team received initial funding of $4 million for Phase 1 R&D with an option of up to 9 million additional dollars. on the performance of the program in the monitoring phases. The team will leverage advances in microbial and biomolecular engineering to develop a scalable bio-separation and purification strategy for rare earth elements (REE) using underdeveloped domestic sources.

REEs are a set of 17 elements from the periodic table which includes the 15 lanthanides plus scandium and yttrium.

Core containing rare earths drilled in La Paz, Arizona. Image courtesy of American Rare Earths Ltd/Photographer Dane Rhys. American Rare Earths is the parent company of project partner Western Rare Earths.

REEs are critical to American competitiveness in a high-tech economy, as they are used in many devices important to the clean energy industry and national security, including computer components, wind turbines, hybrid vehicles/ electronics, LCD screens and tunable microwave resonators. In the defense sector, they are used for lasers, precision-guided weapons, motor magnets and other devices.

To date, the chemical processes required to extract and purify REEs are complex and harmful to the environment. Extracting or recycling REE from new sources, such as low-grade ores and tailings, while using natural products, could be a game-changer for the REE supply chain.

—Yongqin Jiao, LLNL scientist, project principal investigator

Although the United States has sufficient domestic resources of REE, its supply chain is vulnerable due to its reliance on foreign entities for the separation and purification of these elements. “Biomining”, an approach that uses microbes to extract or separate target metals like gold or copper from various sources, is not yet useful for REEs given that the role of REEs in the processes biological was discovered only recently.

In the new project, the LLNL team will leverage the diversity, specificity and customization of environmental microbiology, synthetic biology and protein engineering to enable novel biomining methods for the separation, purification and conversion of rare earths into forms ready for manufacture.

By cultivating novel bioengineered REE-converting bacteria and proteins and translating existing ones, we will provide platform biotechnologies for REE separation and purification with high commercialization potential.

—Dan Park, LLNL scientist, one of the project’s technical leads

In addition to exploiting previously identified microbes and proteins that have been tested and used to purify and separate REEs, the team will conduct a bioprospecting campaign to identify novel REE-associated microorganisms that show potential for use ETRs. The results will expand the repertoire of rare earth biomining hosts and rare earth-binding biomolecules.

The other members of the LLNL team are Dante Ricci, Edmond Lau and Thomas Desautels. Collaborating institutions include Penn State, Columbia University, Tufts University, University of Kentucky, Purdue University and industry partner Western Rare Earths.