The Elements of Innovation Discovered
The Elements of Innovation Discovered
Metal Tech News - April 24, 2024
Leveling up your bowl of curds and whey (also known as cottage cheese!) makes protein fibril sponges that collect gold from an acid bath containing e-waste.
The ingenious process of using whey to recover gold from e-waste.
Aerogel sponge in a beaker loaded with gold ions.
High-purity gold extracted with whey is 50 times more valuable than the cost of the method.
Scientists in Switzerland have recovered high-purity gold through a scalable process using food scrap-derived sponges that efficiently adsorb the precious metal from tricky e-waste.
The final result is 450 milligrams of 22-carat gold recovered from 20 discarded motherboards.
The ingenious process of using whey to recover gold from e-waste.
Because the method utilizes industry byproducts, it is doubly sustainable and cost-effective as well. Gold extracted this way is 50 times more valuable than the cost of the method, requiring only simple machinery such as freeze-drying units and fume hoods to correctly evacuate toxic fumes from the dissolution of e-waste.
The process starts with whey, a byproduct of the cheesemaking industry, to develop a protein fibril aerogel sponge that adsorbs the gold from an acid bath containing e-waste. The collected flakes of gold are then melted, forming a nugget.
"I think the possibility to scale up and make it commercially profitable [is] very high," said project lead Raffaele Mezzenga, professor of materials and health sciences and technology department at ETH Zurich. "And indeed, we are working on it."
Aerogel sponge in a beaker loaded with gold ions.
Inside America's unrecycled e-waste stream awaits billions of dollars of recoverable gold, silver, platinum, and other precious metals – rivaling the gross domestic product of some countries. Add to that a substantial number of critical minerals and we have a healthy urban mining industry waiting to be cashed out.
The Zurich lab report, published in the journal Advanced Materials, compared its gold recovery process to previously reported methods, proposed and proven.
The Swiss whey technique is considered a huge improvement over current methods employing toxic chemicals and more complex, energy-intensive processes.
"[O]ur approach uses food by-products, so the starting raw materials are extremely inexpensive and sustainable," said Mezzenga.
Improved efforts to recycle rare and hard-to-harvest metals from the annual production of more than 59 million tons of e-waste can make the electronics sector more sustainable, pushing back against the tide of waste created by a culture of upgrades and planned obsolescence in smartphones, computers, and other consumer tech.
Mezzenga and his fellow researchers are eager to develop the technology for market. Although the primary feedstock of electronic waste is where they will begin, this technology can mine industrial waste from electronics manufacturing and provide more efficient cleanup after methods like gold-plating.
High-purity gold extracted with whey is 50 times more valuable than the cost of the method.
In addition, similar fibril sponges could be made out of other protein-rich byproducts and waste from the food industry – opportunities are everywhere.
"The fact I love the most is that we're using a food industry byproduct to obtain gold from electronic waste," Mezzenga said in the lab summary.
The utilization of food waste would also prevent it from rotting in methane-producing landfills.
"You can't get much more sustainable than that!" the ETH professor added.
Reader Comments(1)
Eidolon writes:
This is amazing! 450mgs is about $30 worth of gold today. How many motherboards are thrown away each day in Fairbanks, Anchorage, and Juneau? What about the waste from the acid bath?
04/24/2024, 6:44 am