homehome Home chatchat Notifications


Eco-friendly breakthrough extracts gold out of e-waste -- and it's all thanks to cheese

A novel method recovers gold from smartphones, computers and other electronic waste using whey protein.

Tibi Puiu
March 4, 2024 @ 8:24 pm

share Share

Electronic waste
Electronic waste. Credit: Pixexid, Unreal.

In an era where electronic waste grows as rapidly as our reliance on technology, a timely discovery emerges from the laboratories of ETH Zurich in Switzerland. Researchers have found a way to extract gold from the discarded circuits of our digital lives, employing nothing more than a byproduct of cheese production — a bodybuilder’s favorite supplement: whey.

This remarkable method not only promises a more sustainable future for e-waste recycling but also redefines the age-old quest of alchemy, transforming waste into precious metal.

A Modern Alchemy And A Sponge for Gold

How the gold is recovered: Gold ions adhere to a sponge of protein fibrils. (Source: Peydayesh M et al. Advanced Materials, 2024, adapted)
How the gold is recovered: Gold ions adhere to a sponge of protein fibrils. Credit: Peydayesh M et al. Advanced Materials.

At the heart of this process is a simple yet highly effective material: a protein fibril sponge derived from whey. Professor Raffaele Mezzenga and his team from the Department of Health Sciences and Technology at ETH Zurich claim that their e-waste-to-precious-metal conversion is highly efficient, cost-effective, and last but not least, environmentally friendly. That’s in contrast to traditional e-waste recycling which is energy-intensive and more often than not involves highly toxic chemicals to extract the precious metals.

The protein fibril sponges are made by denaturing whey proteins under specific conditions, leading them to form a gel of protein nanofibrils. This gel, once dried, transforms into a sponge capable of selectively adsorbing gold ions from a solution of dissolved electronic components. The beauty of this method lies in its selectivity; while other metals can adhere to the sponge, gold does so more efficiently, making the recovery process both precise and effective.

Upon absorbing the gold ions, the researchers apply heat to the sponge, initiating a reduction process that converts these ions into metallic flakes. These flakes are then melted down to form a gold nugget.

Remarkably, from the components of 20 old computer motherboards, the team successfully extracted a 450-milligram nugget of 22-carat gold, demonstrating the method’s efficiency and potential for scalability.

Towards a Greener Future

Electronic waste, or e-waste, is the fastest-growing waste stream on the planet, according to the World Health Organization. In 2019 alone, the world produced a staggering 53.6 million tonnes of e-waste, with only a meager 17.4% formally collected and recycled. E-waste contains a cocktail of hazardous materials, including lead, mercury, and flame retardants. When dumped in landfills or incinerated, these toxins can leach into the soil and water, contaminating the environment and posing a threat to human health.

The implications of this new technology extend far beyond the laboratory. By providing a method that uses upcycled materials and requires significantly lower energy and financial investment, this new type of recycling paves the way for more sustainable practices in the gold recovery industry. Moreover, it not only addresses the issue of electronic waste but also offers a new lease on life for the byproducts of the food industry.

“The fact I love the most is that we’re using a food industry byproduct to obtain gold from electronic waste,” Mezzenga said in a press release.

Looking ahead, the researchers aim to refine and scale this technology for commercial use. Their vision includes exploring other sources of waste, such as industrial byproducts from microchip manufacturing or gold-plating processes. Furthermore, they are investigating the potential of using other protein-rich waste materials to create the fibril sponges, broadening the scope of this sustainable technology. Perhaps they can tune other sponges to extract other useful metals besides gold, including copper and cobalt.

The findings appeared in the journal Advanced Materials.

share Share

Ronan the Sea Lion Can Keep a Beat Better Than You Can — and She Might Just Change What We Know About Music and the Brain

A rescued sea lion is shaking up what scientists thought they knew about rhythm and the brain

Did the Ancient Egyptians Paint the Milky Way on Their Coffins?

Tomb art suggests the sky goddess Nut from ancient Egypt might reveal the oldest depiction of our galaxy.

Dinosaurs Were Doing Just Fine Before the Asteroid Hit

New research overturns the idea that dinosaurs were already dying out before the asteroid hit.

Denmark could become the first country to ban deepfakes

Denmark hopes to pass a law prohibiting publishing deepfakes without the subject's consent.

Archaeologists find 2,000-year-old Roman military sandals in Germany with nails for traction

To march legionaries across the vast Roman Empire, solid footwear was required.

Mexico Will Give U.S. More Water to Avert More Tariffs

Droughts due to climate change are making Mexico increasingly water indebted to the USA.

Chinese Student Got Rescued from Mount Fuji—Then Went Back for His Phone and Needed Saving Again

A student was saved two times in four days after ignoring warnings to stay off Mount Fuji.

The perfect pub crawl: mathematicians solve most efficient way to visit all 81,998 bars in South Korea

This is the longest pub crawl ever solved by scientists.

This Film Shaped Like Shark Skin Makes Planes More Aerodynamic and Saves Billions in Fuel

Mimicking shark skin may help aviation shed fuel—and carbon

China Just Made the World's Fastest Transistor and It Is Not Made of Silicon

The new transistor runs 40% faster and uses less power.