Chemical ‘Egg-boxes’ Could Crack Rare-earth Element Separations

Access to metals critical to green technologies could be significantly improved thanks to new chemical method, a study shows.

Rare-earth element dependent technologies are crucial for renewable energy generation and storage, electric vehicles, and electronic displays. However, access to these metals, in large part due to difficulties in their separation, is limited and is dominated by China. Improving how rare-earth elements are separated is essential to prevent metal supply derailing climate efforts.

PhD student Joe O’Connell-Danes, Professors Carole Morrison and Jason Love from the School of Chemistry, and Professor Bryne Ngwenya from the School of Geosciences have discovered a new method for separating these valuable elements by using bowl-shaped vessels to spontaneously encapsulate rare-earth compounds. Complementarity between some rare-earths and their fit into the rigid ‘egg-box’ structures results in selective separation.

Significantly, these structures uniquely trap-out lighter rare-earth elements, the major constituents of ores and magnets, allowing for their separation by simple filtration. Importantly, the newly developed process can be run in the same conditions as currently industrialized separation processes.


We have exploited fundamental chemical recognition principles to design a new, recyclable, and highly selective process of separating rare-earths that could be integrated into current metal extraction and recycling industries.