The meteoric advances in computers, cell phones and electronics in general have resulted in a lot of outdated gadgets either ending up in landfills, expensive recycling operations or third world countries where components are burned off or treated with harsh chemicals, to extract the minute amount of gold, silver, copper and other metals that are used in the printed circuit boards. This also releases many other hazardous materials that are used in the electronics and is not good for the people working on extracting the metals and the environment. The EE Times reports that a company in Finland has come up with a biological solution to extract some of these metals. VTT Technical Research Centre has found that mushrooms can extract 80% of the gold from electronic scrap.

"Further crushing, sieving, and flotation (a separation method that separates hydrophobic particles from hydrophilic particles by blowing air into the sludge) resulted in a fraction with high concentration of valuable metals for solution extraction experiments. The researchers say their flotation technique raised the copper content of the circuit board fraction from 25% to 45%, while gold content increased by a factor of 1.5.

"Because it is difficult to remove the components from the circuit boards, the first step in most recycling processes is to crush everything into particulates and that's how we start, too," explains Jarno Mäkinen, research scientist at VTT. "But then, using non-toxic water-based solutions, we have managed to engineer mycelium-based biomass that acts as a biosorbent specifically targeted at gold complexes."

Using biosorbents such as fungal and algae biomass, the Finnish lab demonstrated that more than 80% of the gold in the solution adhered to the biomass, compared with only 10% to 20% of gold recovery when using most commonly used harmful chemical preparations."

This like the current methods will require an industrial scale (the average Joe isn't going to crush his old cell phone or RAM and get any gold or silver), but its not a bad deal if you can extract some of these metals in an environmentally friendly way.

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