In a groundbreaking study, researchers from ETH Zurich have unveiled a novel method for extracting gold from electronic waste, utilizing an unexpected ingredient: a byproduct of cheese production. This innovative approach promises to revolutionize the recycling industry by turning electronic scrap into valuable gold nuggets.
The genesis of gold formation has long fascinated scientists. While it’s understood that gold forms deep within the Earth’s crust under intense pressure and temperature, and later rises through liquid solutions, the precise mechanisms behind its natural accumulation remain elusive. Researchers led by Christopher Voisey from Monash University in Melbourne have made strides in unraveling this mystery, shedding light on how gold deposits might form in nature.
According to Voisey’s team, earthquakes and quartz play pivotal roles in gold accumulation—a hypothesis that has been speculated but not previously validated. Quartz, a mineral known for its chemical inertness and piezoelectric properties (which generate electrical charges under pressure), is central to this new theory. The researchers discovered that during seismic activity, the pressure exerted on quartz crystals generates electrical charges that attract dissolved gold, leading to its deposition on the mineral’s surface.
To test their hypothesis, the team simulated earthquake conditions in the lab by applying pressure to quartz crystals and passing a solution containing dissolved gold and gold nanoparticles over them. The results were striking: the quartz’s electrical activity was indeed sufficient to precipitate gold from the solution, confirming the role of earthquakes and quartz in gold formation. The presence of gold nanoparticles further enhanced this process, suggesting they play a crucial role in the development of gold veins.
This research not only deepens our understanding of gold formation but also offers practical applications. By harnessing these natural processes, the new method could significantly improve the efficiency of gold extraction from electronic waste. As a testament to the potential of this approach, the largest gold nugget ever found weighed 72 kilograms and was discovered in Australia in 1869, with the most recent significant finds being much smaller.
This innovative extraction technique aligns with the growing trend of utilizing unconventional resources for precious metal recovery, potentially reshaping how we approach recycling and resource management in the tech industry.