This ‘chemical sponge’ sucks up the valuable minerals in polluted water

So-called rare earth elements aren’t actually rare. It’s just difficult to refine them into the purified forms that are needed for making things like electronics or clean energy tech. The standard processes are also toxic, which is one reason that the world has outsourced production to China.

Supra, a startup that spun out of the University of Texas at Austin, is taking a different approach that’s clean, low-cost, and makes it possible to capture some of the billions of dollars’ worth...