Scottish scientists have developed a new method for recovering gold from old gadgets such as mobile phones, TV’s and computers, which not only doesn’t require the use of toxic chemicals, such as cyanide, but it is also said to be more effective than current techniques.
According to the researchers from the University of Edinburgh, who have just published their findings in the journal Angewandte Chemie, their extraction method could help recover about 300 tonnes of the precious metal used in electronics each year.
They estimate that electrical waste contains as much as 7% of all the world’s gold as the precious metal is a key component of the printed circuit boards found inside most modern devices.
The team’s proposed technique involves submerging printed circuit boards in a mild acid to dissolve the metal parts, before adding an oily liquid containing the team’s chemical compound. That solution then helps extract gold selectively from the complex mixture of other metals, the researchers say.
The findings could aid the development of methods for large-scale recovery of gold and other precious metals from waste electronics, the team says.
“We are very excited about this discovery,” Professor Jason Love, who led the research, said in a statement. “We have shown that our fundamental chemical studies on the recovery of valuable metals from electronic waste could have potential economic and societal benefits.”
The study, funded by the Engineering and Physical Sciences Research Council, is one of many staff and student-led initiatives at the University of Edinburgh to promote the so-called “circular economy,” which encourages reuse of materials and greater resource efficiency.