Scientists use whey protein to extract gold from circuit boards

We throw them away and buy new ones, then waste the raw materials? More and more companies are committing to technologies that allow reusing or saving resources. Last year, for example, the European Parliament passed a new regulation banning permanently attached batteries from 2027. The move aims to ensure more sustainability for smartphones, laptops and other devices. Scientist Rafael Mezenga from the Department of Health Sciences and Technology and his team are now going one step further. They discovered that sponges made from whey proteins are good for recycling.

The byproduct should aid in recycling

Scientists discovered that the food byproduct is suitable for recovering gold from electronic waste. This makes the recycling process much easier and more efficient. In addition, the energy costs of this process are 50 times lower than if the gold was extracted electrolytically. Mezzenga and his team found they could extract about 450 milligrams of gold from twenty motherboards using the whey protein method.

Whey proteins are a by-product of dairy products that seem exceptionally well-suited for extracting minerals from electronic components. To do this, scientists working with Rafael Mezenga denatured whey proteins in an acid bath at high temperatures until the material turned into a gelatinous substance. The mass is then dried and shaped into a sponge.

Before using whey proteins, e-waste is also prepared and dissolved in an acid bath to ionize the metals. In the next step, the whey product is added to the bath, where the ionized minerals adhere to the protein sponge. Most metals can be extracted this way, but this works best with gold, Mezenga says. To release the metal from the sponge, it is heated to a suitable temperature until the gold ions turn into flakes. The extracted gold was melted down to a mass of 91 percent gold and 9 percent copper, equivalent to 22 carats.

Source: via Tom's devices