Transforming Trash into Treasure

Transforming base materials into gold was a pursuit that fascinated the alchemists of ancient times. While the dream of transmuting elements may remain elusive, Professor Raffaele Mezzenga from ETH Zurich has achieved a remarkable feat in a similar vein. Instead of turning one element into another, he has successfully recovered gold from electronic waste using a surprising ingredient derived from the cheesemaking process.

Electronic waste, such as old smartphones and computers, contains a treasure trove of valuable metals like copper, cobalt, and notably, gold. With the increasing demand for this precious metal, finding efficient and sustainable methods to extract gold from e-waste is crucial. Traditional recovery techniques are often energy-intensive and involve the use of hazardous chemicals. However, Professor Mezzenga and his team have introduced a groundbreaking approach that is not only highly effective but also environmentally friendly.

In a laboratory experiment, the researchers dismantled 20 computer motherboards to access the metal components. These parts were then dissolved in an acid solution to ionize the metals, making them easier to extract. The key innovation lies in the use of a sponge made from a protein matrix, which proved to be remarkably adept at capturing the gold particles from the electronic waste.

Looking ahead, the team aims to further refine the technology for commercial applications. While electronic waste serves as the primary source for gold extraction, there are other potential sources to explore, such as industrial waste from microchip manufacturing or gold-plating processes. Additionally, the researchers are investigating the possibility of creating protein fibril sponges from alternative protein-rich byproducts or waste materials from the food industry.

Professor Mezzenga emphasizes the sustainability aspect of their method, noting that they are utilizing a byproduct from the food industry to recover gold from electronic waste. This innovative approach not only addresses the pressing issue of e-waste management but also demonstrates a circular economy model by transforming waste products into valuable resources. As Professor Mezzenga aptly puts it, "You can't get much more sustainable than that!"