The rare earth elements that help power electric vehicles, wind turbines, medical imaging machines and other advanced technologies may be hiding in an unlikely place: industrial wastewater.

Rice University researchers have developed an ultraporous material capable of pulling several valuable rare earth elements from complex waste streams, a potential step toward recovering critical minerals that might otherwise be discarded. The research was published in ACS Applied Materials & Interfaces.

The approach uses metal-organic frameworks, or MOFs—Nobel Prize–winning materials built from metals and organic molecules into extraordinarily porous structures—and modifies their internal surfaces so they preferentially grab rare earth elements. The researchers tested the material on neodymium, gadolinium and dysprosium, three rare earth elements important to magnets and other technologies.