Highlights

• Germany's TU Clausthal successfully operated a continuous hydrometallurgical system producing 10 kg of rare earth oxalates from 42.5 kg of slag with over 90% recovery efficiency, marking a critical shift from laboratory batch experiments to industrially scalable process engineering.
• The EU-funded HARMONY project (€15M) is de-risking rare earth recycling technology by proving technical feasibility under industrial conditions, though economic viability, feedstock diversity, and integration into Europe's fragmented processing landscape remain unresolved challenges.
• This pilot-scale demonstration signals that European rare earth recycling is transitioning from theoretical possibility to manufacturing reality, providing a credible proof point as magnet waste volumes rise and ESG pressures intensify, though it doesn't threaten China's current dominance.

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Rare earth recycling in Europe has long lived in the laboratory—important, promising, but distant from industrial reality. A new pilot-scale demonstration under the HARMONY project (opens in a new tab) suggests that phase may be ending.

Researchers at Econiche Universität Clausthal (opens in a new tab) (Germany) have successfully operated a continuous hydrometallurgical recycling system, producing 10 kg of rare earth oxalates from 42.5 kg of REE-containing slag. This is not a bench-top curiosity. It is a controlled, multi-reactor process run under industrially relevant conditions.

Why This Milestone Matters (and Why It’s Being Watched)

The headline number—10 kg of oxalates—matters less than how it was achieved. Continuous leaching and selective precipitation with reported recovery efficiencies above 90% mark a shift from batch experiments to process engineering.

For Europe’s rare earth supply chain, that distinction is critical. Continuous operation allows assessment of throughput stability, process control, and scale-up behavior—issues that typically derail promising recycling concepts before commercialization.

In short, this is one of the clearest signals yet that European rare earth recycling is moving from theory toward manufacturability.

The HARMONY Project: Who’s Behind the Work

Launched in 2021, the HARMONY project (opens in a new tab) is a multi-partner EU-funded research initiative focused on circular raw materials and advanced recycling pathways for critical minerals, including rare earth elements. The project has received approximately €15 million in total funding, largely supported through the European Union’s Horizon Europe framework, with additional national research contributions.

HARMONY’s mandate is not production—it is de-risking: proving technical feasibility, understanding process limits, and generating data that industry can trust.

So What’s Solid—and What’s StillAspirational

What holds up:

• Continuous hydrometallurgical operation demonstrated
• High reported recovery efficiencies
• Industrially relevant process controls (pH, temperature, residence time)

What remains unresolved:

• Feedstock diversity (slag is not magnets or e-waste)
• Economic viability at commercial scale
• Integration into Europe’s fragmented downstream REE processing landscape, and don’t underestimate this trek.

The project’s own language remains appropriately cautious. Claims of “strategic autonomy” are directional, not declarative—and that restraint strengthens credibility.

The Bigger Signal for Investors

This is not a threat to China’s dominance. But it is a credible proof point that Europe is learning how to recycle rare earths at scale—knowledge that will matter as magnet waste volumes rise and ESG pressures intensify.

The quiet takeaway: recycling is no longer hypothetical.