Over 50 million tons of electronic waste are generated around the world every year and 80 percent of that ends up in landfills. Researchers from the University of Saskatchewan (U of S) have come up with the way to extract gold from electronic waste, helping boost recovery and recycling efforts.
Stephen Foley, a U of S Chemistry Department associate professor, teamed up with Loghman Moradi, a research associate, and Hiwa Salimi, a PhD student, to come up with a gold extraction method that is not only financially viable but environment-friendly as well.
"This could change the gold industry," said Foley.
The problem with gold is that it's not a reactive chemical element. This makes it hard to dissolve, making extraction and recovery difficult. Commonly, mining for gold calls for massive amounts of sodium cyanide, which is bad for the environment. Gold can also be acquired by recycling electronic scraps, such as circuits and computer chips but the process is costly and also hurts the environment.
Current practices devastate the environment so Foley and his team sought out an alternative. Their solution? A solution combining acetic acid with small amounts of another acid and an oxidant. With it, gold extraction can be carried out under conditions mild enough so as not to hurt the environment, but still efficient enough that the element is dissolved in record time.
In fact, stripping gold from circuits at about 10 seconds is the fastest rate ever recorded.
To extract a kilogram of gold from circuit boards, the typical method will require 5,000 liters of aqua regia, a nitric acid-hydrochloric acid mixture. With the new method, just 100 liters of the researchers' solution will be needed. At 50 cents a liter, the solution needed to extract a gold kilogram would just cost $50 ,and all of it can still be recycled all over again.
Cheaper, quicker, safer, the solution Foley and his team developed could revolutionize gold extraction. The next step for the researchers is to work on integrating the solution into larger-scaled applications needed for recycling gold.
Photo: Reilly Butler | Flickr
