Microbial Advancements in Rare Earth Element Processing: Progress Since 2021

Highlights

• DARPA’s EMBER program aims to develop environmentally friendly microbial technologies for extracting rare earth elements, reducing reliance on foreign processing.
• Collaborative research efforts between universities, national labs, and defense agencies are advancing bio-separation techniques for critical material recovery.
• Emerging bio-mining technologies could potentially disrupt China’s rare earth processing monopoly and strengthen U.S. domestic supply chains within 10-15 years.

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In 2021, DARPA launched (opens in a new tab) the EMBER (Environmental Microbes as a BioEngineering Resource) (opens in a new tab) program to address the U.S. reliance on foreign processing of rare earth elements (REEs). EMBER aimed to develop environmentally friendly and scalable bio-mining technologies using engineered microbes to extract and separate REEs from ores. This approach sought to reduce the environmental and economic costs associated with traditional chemical-intensive methods, which had deterred U.S. domestic processing capabilities.

Developments Since 2021

Since the EMBER program’s inception, advancements in using microbes for REE processing have been promising. Research efforts have demonstrated microbial capabilities in bio-leaching and bio-separation of REEs, with several pilot projects showcasing scalable, low-toxicity extraction methods. Key milestones include:

Milestone	Summary
Enhanced Microbial Engineering	Scientists have improved microbes’ efficiency in binding and separating REEs through genetic modifications, optimizing their adaptability to different ore types.
Pilot Projects	Collaborations between academia, defense agencies, and industry have led to pilot-scale implementations of bio-mining processes, focusing on domestic deposits such as those at Mountain Pass, California.
Environmental Validation	Studies have validated the environmental benefits of microbial methods, including reduced water usage and lower emissions compared to conventional techniques.

Implications for Industry and Defense

The advancements in microbial REE processing have the potential to strengthen the U.S. supply chain for critical materials used in defense technologies, including lasers, guided weapons, and motor magnets. Companies such as MP Materials and Lynas Rare Earths, along with emerging biotech firms, are exploring partnerships to integrate bio-mining into their operations.

Beyond rare earths, DARPA’s focus on microelectronics remains pivotal. Efforts to innovate beyond the “plateau” of current semiconductor technologies, including 3D chip designs and specialized materials, align with the Department of Defense’s push to secure technological dominance.

While microbial REE processing is not yet at full commercial scale, EMBER has demonstrated a viable path forward, offering a sustainable, domestically controlled solution for securing critical materials essential to both defense and industry.

San Diego State University and DARPA Initiative

San Diego State University (SDSU), in collaboration with the University of California, Berkeley, and Pacific Northwest National Laboratory (PNNL), in 2023 reported (opens in a new tab) the spearheading of a DARPA-funded initiative under the EMBER program to create environmentally friendly methods for extracting rare earth elements (REEs).

Principal investigator Marina Kalyuzhnaya (opens in a new tab) was named to head the project, aiming to develop sustainable biofiltration technologies that utilize modified bacteria to recover REEs like lanthanum and neodymium, critical for technologies such as electric vehicles and solar panels.

The project leverages methane-consuming bacteria naturally adapted to extreme conditions, that require REEs for enzymatic processes. Researchers will reverse-engineer these bacteria to produce designer proteins capable of binding selectively to lanthanides. These proteins will be incorporated into biofilters, enabling the extraction of REEs from mine tailings, which are waste products rich in recoverable materials.

Key collaborators include Xerox’s Palo Alto Research Center (PARC), which will bioprint porous sorbent materials for scalable biofilters, and startup Phoenix Tailings, which will refine recovery methods. Environmental engineer Christy Dykstra (opens in a new tab) emphasized that the system aims to be low-energy, solvent-free, and self-renewing, offering a cleaner alternative to traditional extraction methods.

The project’s proof-of-concept is expected within four years. It will provide SDSU students with valuable multidisciplinary research experience. If successful, the technology could revolutionize REE recovery, reducing reliance on environmentally harmful practices and bolstering domestic supply chains critical for advanced technologies.

Rare Earth Exchanges will continue to track possible breakthrough approaches to disrupt the rare earth element separation and refining process.

Advancements in Rare Earth Processing?

American Rare Earths (opens in a new tab) (ARR) reported last June significant metallurgical breakthroughs in collaboration with Lawrence Livermore National Laboratory (opens in a new tab) (LLNL) and the University of Kentucky (opens in a new tab) as part of the DARPA-funded SynBREE (opens in a new tab) project. The research focuses on enhancing the extraction and processing of rare earth elements (REEs) at the Halleck Creek deposit in Wyoming, aiming to secure a stable U.S. domestic supply of these critical materials.

Key results include:

• Preconcentrating Halleck Creek ore to 3.5% total rare earth oxides (TREO) using low-cost Dense Medium Separation (DMS), achieving a 12:1 upgrade ratio and a ~200% efficiency improvement over existing methods.
• Reducing Wet High-Intensity Magnetic Separator (WHIMS) requirements by 70%, significantly lowering capital and operational costs.
• Cutting the feed mass for direct leaching by 56%, further reducing costs and resource usage.

Do these findings enhance economic viability and sustainability by leveraging protein-based rare earth separation technologies alongside conventional beneficiation techniques? If commercially feasible, such advances could secure a domestic supply of rare earths essential for technologies like electric vehicles, solar panels, and defense systems.

CEO Donald Swartz highlighted the project’s role in addressing critical U.S. supply chain gaps and its potential to establish Halleck Creek as a world-class resource. Dr. Yongqin Jiao (opens in a new tab) of LLNL emphasized the efficiency gains from integrating low-cost density and magnetic separation methods with bio-separation processes.

Again, the SynBREE project, supported by DARPA’s EMBER program, includes leading academic and research institutions like the University of Kentucky, Penn State, and Columbia University. It drives innovation in REE processing and contributes to U.S. energy and national security priorities. ARR aims to integrate these breakthroughs into its operations to support the clean energy transition and ensure resource independence.

Timeline

The commercialization of biological approaches to refining rare earth elements (REEs), developed under DARPA’s SynBREE and EMBER programs, is expected to take approximately 10 to 15 years to scale fully. Currently, these programs are in the proof-of-concept phase, focusing on demonstrating the feasibility of bio-mining and bio-separation technologies. Over the next 2 to 4 years, pilot studies will aim to validate these methods’ economic and environmental advantages compared to traditional chemical-intensive techniques. Once proven, the next phase will involve scaling to pre-commercial facilities, which will likely take another 3 to 4 years. This step includes optimizing microbial productivity, ensuring consistent REE recovery, and addressing regulatory and logistical challenges.

Full-scale commercialization, expected within 8 to 15 years, will require significant investment in infrastructure, workforce training, and the integration of bio-based processes into existing mining operations. Success will depend on overcoming technical hurdles, navigating regulatory approvals, and ensuring industry collaboration. Government support, such as continued funding from DARPA and the Department of Energy, coupled with private sector investments, could accelerate adoption. However, delays may arise due to scalability challenges or resistance from industries already entrenched in traditional methods.

If realized, these bio-based technologies could disrupt China’s near-monopoly on rare earth processing, bolstering the sustainability and security of the U.S. supply chain.

This transition would represent a transformative shift, ensuring a stable domestic supply of critical materials for clean energy technologies and national defense. However, again, the U.S. still faces tremendous vulnerability due to a less-than-resilient rare earth element supply chain.