Rare earth elements await in waste

Rare earth elements are hard to get and hard to recycle, but a flash of intuition led Rice University scientists toward a possible solution.

The Rice lab of chemist James Tour reports it has successfully extracted valuable rare earth elements (REE) from waste at yields high enough to resolve issues for manufacturers while boosting their profits.

The lab’s flash Joule heating process, introduced several years ago to produce graphene from any solid carbon source, has now been applied to three sources of rare earth elements -- coal fly ash, bauxite residue and electronic waste -- to recover rare earth metals, which have magnetic and electronic properties critical to modern electronics and green technologies.

The researchers say their process is kinder to the environment by using far less energy and turning the stream of acid often used to recover the elements into a trickle.

The study appears in Science Advances.

Rare earth elements aren’t actually rare. One of them, cerium, is more abundant than copper, and all are more abundant than gold. But these 15 lanthanide elements, along with yttrium and scandium, are widely distributed and difficult to extract from mined materials.