Highlights

• Genetically engineered yeast produces bio-based oxalic acid that recovers over 99% of rare earth elements from mineral solutions, directly challenging China's chemical processing dominance in the global supply chain.
• The breakthrough enables cheaper, cleaner rare earth processing at ~$1.79/kg with 100%+ carbon intensity reductions compared to fossil-based methods, eliminating costly purification steps by using crude fermentation broth directly.
• While laboratory-scale and not yet commercial, this Nature Communications study opens a credible alternative pathway that could enable Western nations to reduce dependence on Chinese chemical inputs and build localized processing capacity.

---

A new Nature Communications study demonstrates a sustainable—but still early—path for rare earth recovery. A multidisciplinary research team led by Jingxia Lu (opens in a new tab) and Huimin Zhao (opens in a new tab) at the University of Illinois Urbana-Champaign (opens in a new tab), working with collaborators from Lawrence Livermore National Laboratory (opens in a new tab) and the University of Kentucky (opens in a new tab), has published a notable new study in Nature Communications. The paper demonstrates that a genetically engineered yeast can produce bio-based oxalic acid capable of recovering more than 99% of rare earth elements (REEs) from mineral solutions—directly addressing one of China’s most durable advantages in the global rare earth supply chain: chemical processing dominance.

Why Oxalic Acid Matters—and Why China Dominates

Rare earth elements are geologically widespread, but processing them into usable forms is exceptionally difficult. China’s dominance does not primarily rest on mining alone; it is reinforced by decades of investment in downstream separation chemistry, including large-scale production of oxalic acid, a critical reagent used to precipitate and purify rare earths during refining.

Huimin Zhao, Steven L. Miller Chair, Professor

Today’s oxalic acid is largely fossil-derived, energy-intensive, and environmentally burdensome to produce. These factors have discouraged Western refiners from building competitive processing capacity and have further entrenched China’s scale advantage.

The study poses a simple but consequential question: What if the chemistry itself could be redesigned—cheaper, cleaner, and closer to where rare earths are processed?

Study Methods, Explained for a Broad Audience

The researchers engineered a low-pH-tolerant yeast, Issatchenkia orientalis, to biologically produce oxalic acid through fermentation—conceptually similar to industrial brewing, but optimized using modern metabolic engineering.

Key methodological innovations included:

• Introducing new metabolic pathways enabling efficient oxalic acid production
• Running fermentation at acidic pH levels compatible with real rare earth processing conditions
• Using the crude fermentation broth directly eliminates the need for costly oxalic acid purification

This integration is crucial: purification accounts for a large share of oxalic acid’s cost and environmental footprint in conventional processes.

What the Study Found

The results are technically robust and industrially relevant:

• >99% recovery of neodymium (Nd) and lanthanum (La), and >98% recovery of dysprosium (Dy) from individual solutions
• >99% total rare earth recovery from a low-grade allanite ore leachate, even with common impurities present
• Performance matched commercial oxalic acid, despite using unpurified bio-derived material
• Structural analyses (XRD and FTIR) confirmed that the recovered rare earth oxalates were chemically and crystallographically equivalent to conventional products

Economic and environmental modeling further showed:

• An estimated minimum selling price of ~$1.79/kg, within current global market ranges
• Carbon intensity reductions exceeding 100% relative to fossil-based oxalic acid under certain electricity-displacement assumptions

In plain language: the chemistry works—and it could be cheaper and cleaner.

Strategic Implications: A Crack in the Processing Wall

This research targets the true chokepoint in rare earth supply chains: processing chemistry, not ore availability.

If scaled successfully, bio-based oxalic acid could:

• Reduce dependence on Chinese chemical inputs
• Enable localized or allied-nation rare earth processing
• Lower environmental, permitting, and regulatory barriers for Western refiners

Rather than competing mine-to-mine, the work suggests a subtler strategy: undermining China’s advantage at the chemical level.

Limitations and Open Questions

The authors are clear—and REEx concurs—this is not yet an industrial solution.

Key limitations remain:

• The system is laboratory-scale, not commercial-scale
• Long-term strain robustness and continuous operation remain unproven
• Integration with real mining operations introduces logistical and regulatory complexity
• Economic models assume favorable feedstocks and power structures that may not apply universally

More broadly, chemistry alone does not dismantle monopolies. China’s dominance is reinforced by infrastructure depth, permitting speed, workforce expertise, and state coordination—advantages biology cannot erase overnight.

Conclusion: A Real Scientific Advance—Not a Silver Bullet

This study does not end China’s rare earth dominance. But it does something arguably more important: it opens a credible, scientifically validated alternative pathway where none previously existed.

By attacking the chemical chokepoint with biology, the authors show that rare earth processing need not remain locked into fossil-based, China-centric systems indefinitely. Whether this breakthrough evolves into a strategy or remains an elegant proof of concept will depend on policy alignment, capital discipline, and industrial execution.

Citation: Lu J. et al. “Bio-based oxalic acid production in Issatchenkia orientalis enables sustainable rare earth recovery (opens in a new tab).” Nature Communications (2026).