U.S.-developed process could simplify rare earth production and reduce dependence on China.
Rare earth elements are critical components in a wide range of modern technologies, from smartphones and air conditioners to the electric motors that power vehicles. However, the growing global demand for these materials is met by a supply chain dominated by a single player: China. The country not only leads in the mining of rare earths but has an even tighter grip on their processing and refinement. Current separation technologies, developed in China, are highly energy-intensive, involve multiple complex steps, and rely on chemicals that can harm the environment.
Now, researchers in the United States have developed a promising alternative that could significantly improve domestic access to these vital resources. According to Interesting Engineering, this innovation represents a breakthrough. Developed at the University of Texas at Austin, the new method takes inspiration from biological systems and their selective filtering mechanisms. Human cells, for example, use specialized proteins to allow certain ions through while blocking others—a concept that the researchers have adapted to separate rare earth elements.
Tiny Gatekeepers That Let Only Rare Earths Through
Drawing on this biological model, the team engineered synthetic membrane channels using nanoscopic pores. These nanopores are built around structures called pillararenes—ring-shaped organic molecules. The scientists modified these molecules to block common ions like potassium, sodium, and calcium from passing through aqueous solutions, while selectively allowing rare earth ions such as europium and terbium. Terbium is particularly critical, as its separation is especially difficult, and China holds an overwhelming share of its production.
The membrane channels demonstrated remarkable selectivity, far surpassing traditional solvent-based methods, which require dozens of steps to achieve similar results. The next goal is to integrate this technology into a scalable system suitable for industrial applications. The research team is currently developing a platform capable of transporting not only rare earth ions but also other strategically important elements like lithium and gallium. Their ultimate aim is to enable more efficient and environmentally sustainable resource extraction in the U.S.
While this marks a major step forward, it still falls short of full independence from China’s rare earth supply chain. In addition to mining and refining, China dominates the further processing of rare earths into high-performance magnets and other advanced materials. The U.S. is only beginning to build these capabilities.
More Innovation: Globally, researchers are exploring new ways to improve rare earth processing. Previous reports have highlighted efforts using molecular “sponges” and even microbes. China, the current market leader, is also pushing ahead with its own innovations, such as faster production techniques using electric currents.
Photo: Andrey Prokhorov via Canva