University of Chicago Separates Neodymium to 97% Purity Using Water-Based Atomic Channels

Highlights

• Researchers used magnesium-pinned manganese oxide channels to boost neodymium-over-lanthanum enrichment from 1.6-fold to 5.4-fold, reaching 97% purity in two cycles.
• The aqueous, solvent-free method published in Nature Chemical Engineering targets a major Western vulnerability in rare earth separation and purification.
• The technique exploits tiny differences in hydration shell dimensions across lanthanides for atomic-level selectivity without organic solvents.
• Industrial viability remains unproven—throughput, energy consumption, material lifetime, and cost per kilogram at scale have not yet been established.
• REEx views this as a breakthrough in separation mechanism, not a commercial flowsheet, with further testing across additional lanthanides ongoing.

A U.S. research team has demonstrated a potentially cleaner method for separating rare earth elements—one of the West’s toughest industrial bottlenecks. Researchers at the University of Chicago, Northwestern University and Argonne National Laboratory used angstrom-scale channels in layered manganese oxide, aqueous chemistry and electrochemistry to discriminate among chemically similar lanthanides. Adding magnesium to “pin” the channels increased neodymium-over-lanthanum enrichment from 1.6-fold to 5.4-fold; after two purification cycles, the researchers report obtaining 97% pure neodymium. Published in Nature Chemical Engineering (opens in a new tab), this is significant separation science. It is not yet an industrial process.

REEx Insight | 97% Is Impressive—Scale Is the Real Test

This research attacks precisely the right problem. China’s rare-earth advantage extends far beyond geology: separation and purification remain major Western vulnerabilities. The clever part is atomic-level selectivity. Dissolved rare-earth ions carry hydration shells whose dimensions vary slightly across the lanthanides. Researchers engineered manganese-oxide channels only a few water molecules wide, then used magnesium ions to prevent those channels from expanding. Tiny differences between rare-earth ions consequently produced larger differences in binding.

But investors should not leap from 97% laboratory purity to commercial disruption. End-market purity requirements vary, and the UChicago report does not establish industrial throughput, continuous operation, recovery and yield at scale, material lifetime, energy consumption, or competitive cost per kilogram. That is the valley between an elegant paper and a working refinery.

A Different Attack on the Solvent-Extraction Bottleneck

Conventional rare-earth separation typically relies on complex, multistage solvent-extraction circuits. This experimental method instead operates in water without organic solvents—a potentially important environmental and process advantage if it scales. The researchers appropriately acknowledge that it is not ready to replace industrial purification. Testing across additional lanthanides continues. For REEx, that restraint strengthens the story. The breakthrough here is a separation mechanism, not yet a commercial flowsheet.

REEx Connect

University of Chicago Pritzker School of Molecular Engineering — Assoc. Prof. Chong Liu, senior author; Siqi Zou and Jiadong Liu, co-first authors.

Northwestern University — Prof. George Schatz; Woo Cheol Jeon, co-first author.

Argonne National Laboratory — Collaborator providing experimental X-ray characterization.

Authors

Study: “Pinning Angstrom-size solid ionic channel for the separation of rare earth elements,” Nature Chemical Engineering, July 21, 2026.

REEx Bottom Line: America needs more than separation capacity. It needs better separation technology. This is promising science; scale, economics and industrial durability come next.