Researchers develop an economically viable method to recover gold from electronic waste
الذهب المستخرج تم تجربته كمادة حفازة في صناعة بعض الأدوية
Researchers develop an economically viable method to recover gold from electronic waste
Successive Sustainable Development challenges require finding new and innovative approaches and solutions; To benefit from everything, including waste, and perhaps electronic waste is one of the promising sources for recovering a group of important precious metals for reuse again.
Researchers from the University of Cagliari in Italy looked into finding a sustainable and economically viable way to recover gold from electronic waste, which could be used as a catalyst in the pharmaceutical industry. This is with the aim of preventing its waste in landfills and reducing the need for mining new materials.
Catalysts (auxiliaries), as we studied when we were young, are materials - often made from rare metals - that are involved in reactions; To change its rate “speed”; This is without being involved in itself or changing chemically. Catalysts currently used in most industries are extracted using expensive, energy-intensive, and resource-destroying mining processes.
Joint research cooperation for an economically feasible method
The method of extracting gold from waste was developed by researchers at the University of Cagliari in Italy, while researchers at Imperial College London developed a method to use this gold recovered from waste, as the study was published in the ACS Journal of Sustainable Chemistry and Engineering.
Waste electrical and electronic equipment is usually sent to landfills, where separating and extracting the components requires a lot of energy and strong chemicals; Which undermines the economic viability of the mineral recovery process. However, electronic waste contains a wealth of minerals that can be used in a range of new products, so finding ways to recover these minerals and use them in a low-cost, low-energy and non-toxic way is crucial; To make our use of electronic goods more sustainable.
Lead researcher Professor James Wilton Ely, from the Department of Chemistry at Imperial, said: “It is shocking that most of our e-waste is going to landfill, and it is the opposite of what we should be doing to look after our precious basic resources. The new approach developed aims to reduce waste already existing within our communities and make them valuable resources for making catalysts; Thus also reducing our dependence on environmentally harmful mining practices.”
He also added: “Consumer behavior is currently pushing us to increase our electronic waste, but methods like the one we developed can help recast this waste as an important resource. Even obsolete SIM cards, which we routinely discard, have value and can be used; To reduce dependence on mining, this approach has the potential to improve the sustainability of processes such as pharmaceutical manufacturing.”
Professors Angela Serpi and Paola Diplano, from the University of Cagliari, have developed a low-cost method to extract gold and other valuable metals from electronic waste such as printed circuit boards (PCBs), SIM cards and printer cartridges. This patented process includes selective steps for the sustainable recovery of base metals such as nickel, copper, silver, and finally gold.
But it must be noted here that the gold produced from this process is a molecular compound and not pure gold. Therefore, it cannot be reused again in the electronics industry without investing a lot of energy to obtain the gold metal in pure form.
A promising use of recovered gold in the pharmaceutical industry
Seeking to use this compound from recovered gold, the team of Professor Wilton Ely and his colleague Professor Chris Braddock investigated whether the resulting compound could be used as a catalyst in some industries, including pharmaceutical intermediates.
Catalysts are used to increase the rate of a chemical reaction - without changing it - in most production processes. The team tested the gold compound recovered from electronic waste in a number of reactions commonly used in the pharmaceutical industry, for example making anti-inflammatory and pain-relieving drugs, where they found that the performance of the gold compound was similar to or better than the catalysts used in the reactions to make these drugs currently, and that it was reusable; Which increases its sustainability.
The researchers suggest that the new technology they have developed in recovering gold from electronic waste is economically viable, opening up opportunities for uses for other components recovered in this process. For example, copper and nickel are also separated, as well as the plastic itself, with the potential for all of these components to be used in new products.
Shaun McCarthy, a PhD student leading the research at Imperial, said: “By weight, PC contains far more precious metals than the mined ore; Which provides a concentrated source of these minerals, but in a civilized manner compared to traditional mines.”
While Professor Serpe said: “Research such as ours aims to contribute to cost-effective and sustainable metal recovery processes, by building a bridge between the supply of precious metals extracted from scrap (waste A) and different sectors in the industry; To overcome the stage of resorting to the extraction of new minerals.”
The research team is working to expand this technology to include recovering the content of metals such as palladium, and reusing it in expired car catalytic converters (ecoboxes). This is certainly important, especially because palladium is widely used as a catalyst and is more expensive than gold.
