Invention transforms e-waste into 22-carat gold nuggets instead of toxic trash

A research team at ETH Zurich has developed an innovative method to extract nearly pure 22-carat gold from electronic waste using a protein-based aerogel derived from cheese production byproduct, whey, Earth.com reported. This sustainable technique offers a safer and more cost-effective alternative to traditional methods involving toxic chemicals.

The process involves transforming whey proteins into a porous aerogel sponge that selectively attracts gold ions from dissolved circuit boards. Laboratory tests showed the sponge captured gold with about 90.8% purity on the first pass, outperforming conventional plastic resins. Heating the loaded sponge converts gold ions into solid flakes, which fuse into nuggets approximately 91% gold and 9% copper—meeting 22-carat standards.

This method significantly reduces energy and procurement costs, potentially enabling local recycling plants and cutting transportation emissions. Researchers are also exploring similar sponges made from plant-based proteins and fish collagen to recover other valuable metals like copper and cobalt. The approach could transform two waste streams—whey and e-waste—into valuable resources, promoting sustainability and reducing reliance on environmentally damaging mining.