Mine Canada's E-Waste for Metals

Urban mining can recover precious critical minerals from phones, flashlights, laptops and TVs—before they hit the landfill

- Gisele azimi

WHEN I TELL PEOPLE I WORK in urban mining, they sometimes (incorrectly) picture me sporting a hard hat and chipping away at old office towers with a pickaxe. In the past, the main way to obtain in-demand materials—like those precious critical minerals everyone’s fighting over—was through primary mining, digging deep into the ground in remote locations to extract them.

But since 2014, in my chemical engineering lab at the University of Toronto, I’ve been plumbing another abundant source in Canada’s cities: e-waste, a term for the discarded electronics and batteries rusting in our landfills.

For a culture that’s constantly tapping on technology, we rarely think about the untapped resources inside it. Critical elements power many of our modern machines: for example, smartphone and computer circuit boards are rich in copper, gold, silver, indium and tin. Electric motors and wind turbines use magnets with high concentrations of rare-earth elements, like neodymium. And EV batteries are chock full of cobalt, manganese and nickel. Regular miners might be able to extract one or two per cent of a desired element from a small chunk of ore, but in a similarly sized chunk of e-waste—where the rocky impurities are already removed—that concentration can shoot up to 30 per cent.