A New Zealand Startup Is Using Microbes to Suck Solid Gold Out of E-Waste
Microscopic organisms can extract precious metals from discarded devices
The world produces 50 million tons of e-waste each year — equivalent to 4,500 Eiffel Towers or 125,000 jumbo jets — from old computers, discarded screens, broken smartphones, and damaged tablets. E-waste is the fastest growing waste stream in the world, but it also holds metals crucial to tech that could soon become short in supply.
As our reliance on tech increases, there’s a growing need to reduce e-waste while conserving metals vital to building tech products. The solution may lie in the tiniest of organisms: microbes. These microscopic life forms can extract metals such as cobalt, gold, and platinum from the devices we toss into landfills.
“Microbes can facilitate some processes that would otherwise require high temperatures and other extreme conditions,” says Anna Kaksonen, who leads the Biotechnology and Synthetic Biology Group of the Commonwealth Scientific and Industrial Research Organisation, Australia’s national science research agency. “In some cases, they provide a more sustainable alternative than traditional pyrometallurgical or hydrometallurgical processes.”
Pyrometallurgy applies heat to recover metals, while hydrometallurgy uses chemicals. Bioleaching, meanwhile, employs microbes to do the job. It isn’t a novel technique — mining operators use it to extract metals from ores — but it isn’t widely used in e-waste recycling yet because it’s typically slower than conventional extraction and can’t recover as much metal as other methods. However, it holds promise as a greener process for rescuing e-waste, since heat-based methods use a lot of energy and release dangerous gases, and chemical methods produce toxic waste streams.
New Zealand-based startup Mint Innovation is one company attempting to bring microbes to the mainstream. “It came out of the idea that microbes can take a waste product and turn it into something valuable,” says Thomas Hansen, the company’s commercial manager. “Electronics have a…