An Overview of How to Recycle NdFeB Magnets via Recycling Technologies

Highlights

• Less than 1% of rare earth elements are currently recycled globally, with NdFeB magnets playing a critical role in green technologies.
• Multiple recycling methods like hydrometallurgy, pyrometallurgy, and hydrogen decrepitation offer unique advantages and challenges in recovering rare earth elements.
• Future success depends on innovative technologies, regulatory support, and economic incentives to create a sustainable circular economy for rare earth material recovery.

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Professor Muammer Kaya (opens in a new tab) at Eskisehir Osmangazi University (opens in a new tab), in Eskisehir (ESOGU), Turkey delves into the current practice of recycling NdFeB Magnets: the challenges, innovations, and future prospects.

The recycling of NdFeB magnets, a key source of rare earth elements (REEs), is gaining attention due to their critical role in green technologies like wind turbines, electric vehicles (EVs), and electronic devices. Despite their importance, less than 1% of REEs are recycled globally, with challenges stemming from technological inefficiencies, high costs, and lack of incentives.

NdFeB magnets are valued for their high remanence, coercivity, and energy density. However, with natural deposits containing only 5% REEs compared to the 15–30% found in end-of-life (EoL) magnets, recycling presents a compelling opportunity for resource recovery and supply risk mitigation.

The recent output was published in the peer-reviewed Current Opinion in Green and Sustainable Chemistry (opens in a new tab)/

Kaya breaks down state-of-the-art recycling methods for the reader, with Rare Earth Exchanges:

Recycling Methods	Pros	Cons
Hydrometallurgy	Efficient for low-grade materials.High purity of recovered REEs.Lower environmental impact compared to pyrometallurgy.	Generates substantial sludge and wastewater.High reagent and energy consumption.Long processing times with multiple steps.
Pyrometallurgy	Applicable to high-grade materials.Fewer processing steps than hydrometallurgy.Suitable for oxidized alloys.	High energy demands.Environmental impact from emissions and waste.REE concentration in slag complicates recovery.
Hydrogen Decrepitation (HPMS)	Eco-friendly, low energy and chemical use.High recovery efficiency.Shorter recycling loops, suitable for industrial use.	Limited use with mixed or oxidized scraps.Requires additional optimization for scale-up.

What are some Challenges in Recycling

Challenges	Summary
Technological Barriers	Efficiently handling heterogeneity in magnet compositions and dealing with brittleness and oxidation.Complex dismantling processes, often requiring extensive labor or specialized robotic systems.
Economic Viability	Primary REEs remain cheaper than recycled ones due to high recycling costs.Manual dismantling of small devices is labor-intensive and often uneconomical.
An Overview of How to Recycle NdFeB Magnets via Recycling Technologies Impact	While recycling reduces mining waste, current methods (especially hydrometallurgy) still generate substantial secondary waste.
Policy and Incentives	Lack of regulations mandating recycling and labeling for traceability. Insufficient awareness among manufacturers and consumers about the benefits of magnet recycling.

Innovations and Opportunities

Perhaps taking the best of the different worlds can lead to superior outcomes.  What follows are some potential breakthroughs and opportunities in this unfolding field.

Innovation & Opportunity	Summary
Direct Recycling (Magnet-to-Magnet):	HPMS technology, nearing commercialization in Europe, provides a cost-effective, energy-efficient alternative. Produces high-quality powders for re-sintering into new magnets, minimizing material losses.
Combined Processes	Hybrid recycling methods combining pyro-, hydro-, and HPMS routes can overcome individual limitations and optimize efficiency.
Green Solvents and Biochar	Research into using biodegradable solvents and biochar for leaching is promising for reducing environmental impacts.
Policy-Driven Circular Economy	Establishing recycling quotas, take-back programs, and eco-design standards could facilitate large-scale adoption of NdFeB recycling.

Conclusion

Recycling NdFeB magnets is crucial for securing critical raw materials for renewable energy technologies while mitigating environmental impacts. Despite significant advancements in recycling methods, challenges like cost, scalability, and secondary waste management persist. The path forward involves combining innovative technologies, regulatory support, and economic incentives to create a viable circular economy for NdFeB magnets.

Scaling up efficient and eco-friendly processes like HPMS while improving material recovery rates and reducing costs will be pivotal in achieving sustainable rare earth recycling. Collaboration between governments, industries, and research institutions is essential to address these challenges and harness the full potential of secondary REE resources.