Using a bioengineered protein-based technology, Lawrence Livermore National Laboratory (LLNL) scientists and collaborators will develop a new separation technique that ultimately will increase the concentration of rare-earth elements (REE) so they are more readily available to the defense sector.
Under the Defense Advanced Research Projects Agency (DARPA) Environmental Microbes as a BioEngineering Resource (EMBER) program, the team was awarded an additional $4.6 million in R&D funding for phase 2. The team will use bioengineered proteins to explicitly enhance the biomining workflow and to produce high-value reagents needed for REE processing.
"We will continue our efforts to identify and optimize rare-earth binding proteins for various stages of rare-earth separation," said LLNL scientist and team member Dan Park. "This includes screening naturally occurring proteins and designing proteins de novo."
REEs are a set of 17 elements in the periodic table that includes the 15 lanthanides, plus scandium and yttrium. They are essential for American competitiveness in a high-tech economy because they are used in many devices important to the clean-energy industry and national security, including computer components, wind turbines, hybrid/electric vehicles, LCD screens and tunable microwave resonators. In the defense sector, they are used for lasers, precision-guided weapons, magnets for motors and other devices.
To date, the chemical processes to extract and purify REEs are complex and harmful to the environment. Extracting or recycling REE from new sources, like electronic waste and coal byproducts, while using natural products, like the protein lanmodulin, could be game-changing, according to research members. The protein allows for a one-step quantitative and selective extraction of REEs from electronic waste and pre-combustion coal, something the other chemical extraction methods don't.
"Our protein-based rare-earth separation technologies continue to be advanced. We are poised to discover different flavors REE-binding protein with much greater separation power than those used in traditional solvent extraction methods." said LLNL scientist Yongqin Jiao, principal investigator for the project.
Although the U.S. has adequate domestic REE resources, its supply chain is vulnerable due to dependence on foreign entities for separation and purification of these elements. "Biomining," an approach that uses microbes to extract or separate target metals like gold or copper from a variety of sources, is not yet useful for REEs given that a role for REEs in biological processes has only recently been discovered.
LLNL will use its centralized, high-performance supercomputer facility maintained by Livermore Computing (LC). For the project, the LC facility will be critical for performing machine learning to iteratively design and improve proteins with enhanced REE specificity and affinity. In addition to the LC facility, the LLNL provides research staff experienced at conducting similar protein refinement studies for the design of vaccine antigens and therapeutic antibody design.
Ultimately, the goal is to commercialize the technology for use in the mining, mining technology and REE recycling sectors.
LLNL researchers Ziye Dong, Patrick Diep, Jeremy Seidel, Ed Lau, Fangchao Song and Lin Song are also on the team. The work is funded by the DARPA Environmental Microbes as a BioEngineering Resource program.
