ETH Zurich researchers recover gold from e-waste using whey protein

Researchers at ETH Zurich have developed a novel method to recover gold from electronic waste using whey protein, a byproduct of the dairy industry. The process aims to provide a more sustainable alternative to traditional recycling methods, which often require high energy consumption and hazardous chemicals.

In the experiment, researchers processed 20 circuit boards from old computers to extract metal components into an ionic solution. They then introduced an aerogel made from whey protein nanofibers, created through high temperatures and acidic conditions. This protein sponge selectively attracts gold ions more efficiently than other metals in the solution.

After heating the protein sponge, the gold ions are converted into particles that can be melted. The experiment successfully produced a nugget of approximately 450 milligrams, which was roughly 91% gold and approximately 22 carats in purity. The remaining mass consisted primarily of copper.