Sustainable transformation of rare earth metals value chain for dual-use technologies

Rare earth metals (REMs), including lanthanides, scandium, and yttrium, are crucial for civilian and defense applications owing to their superior magnetic, optical, and catalytic properties. Their strategic importance extends to clean energy, electric vehicles, corrosion protection, agriculture, catalysis, and advanced weaponry. Although abundant in Earth’s crust, rare earth elements (REEs) are geologically dispersed and economically challenging to extract owing to similar ionic properties, creating supply chain risk largely attributed to China’s refinery capacity. In this review, we analyze the entire REM value chain, including classification, global distribution, mining, mineral processing, beneficiation (physical and chemical), leaching, and separation and purification, along with their high-performance applications. The geopolitical impact, market pressures, and processing complexities, including environmental hazards, purity management, and scale-up, are also discussed within the context of international policy responses. In response, strategies such as green metallurgy, closed-loop recycling, and green extraction techniques have been proposed to reduce environmental impact and supply vulnerability. A dual-use perspective is adopted, linking REEs 4f-driven properties to essential roles in both advanced civilian industries and defense technologies. Future pathways such as AI-enabled separation, digital tracking, and circular economy models are identified as routes to resilient and sustainable supply chains. By fostering innovation, diversification, and recycling, nations can reduce reliance on limited suppliers while meeting rising demand, thereby supporting sustainable growth and national security.