E-waste breakthrough: cooking oil-based method offers green solution for silver recovery

E-waste breakthrough: cooking oil-based method offers green solution for silver recovery

  By Faridat Salifu

Researchers in Finland pioneer sustainable recycling of precious metals from electronics

A team of Finnish scientists has developed a groundbreaking technique to recover silver from electronic waste using organic fatty acids found in cooking oils—offering a safer, cost-effective, and environmentally friendly alternative to traditional chemical recycling processes.

The research, conducted by scientists at the University of Jyväskylä and the University of Helsinki, demonstrates that waste-derived fatty acids such as oleic acid—commonly found in used cooking oil—can extract silver from discarded electronics through a low-toxicity, room-temperature process. The method bypasses the need for strong acids, cyanide, or other hazardous chemicals typically used in conventional silver extraction.

Although gold often draws attention due to its high value, silver is far more crucial in modern technologies and the clean energy transition. It is widely used in:

• Photovoltaic solar panels – Silver conducts electricity in 90% of today’s rooftop solar panels, which are central to India’s solar energy expansion. Currently, solar installations across India generate about 108 gigawatts (GW) of electricity—roughly 10% of the country’s coal-generated power.

• Mobile phones – India’s over 1.4 billion mobile phone users rely on devices that each contain between 100 to 200 milligrams of silver, used for conductivity, soldering, and internal circuits.

• Computers and electronics – A typical desktop or laptop computer contains approximately 350 milligrams of silver, essential for circuit boards, connectors, and memory chips.

With silver’s unique conductivity, malleability, and thermal properties, its demand is increasing in both consumer electronics and green technologies.

Traditional e-waste recycling methods rely on smelting or leaching with toxic chemicals like nitric acid and cyanide, which can pose serious risks to human health and ecosystems. In low- and middle-income countries, informal recycling often involves open burning or acid baths, leading to severe environmental pollution and worker exposure to carcinogens.

Additionally, the energy-intensive nature of these processes adds to carbon emissions and operational costs, while inefficient recovery methods leave valuable metals unrecovered.

The Finnish researchers’ use of fatty acids—readily available from waste cooking oils or plant sources—offers a closed-loop solution with several advantages:

• Low environmental impact: The process operates at room temperature and eliminates toxic by-products.

• Cost-effective: Using organic compounds derived from waste reduces dependence on expensive industrial reagents.

• Scalability: The method can be adapted for small and large-scale recovery operations, especially in urban areas with high e-waste volumes.

The team is now working to optimise the method for industrial use, including potential applications in recycling centres and electronics manufacturing hubs. With rising global demand for precious metals and growing pressure to manage e-waste sustainably, innovations like this offer a promising path to circularity in the electronics sector.

The breakthrough aligns with broader global efforts to green the electronics supply chain, reduce landfill pressure, and minimise the environmental cost of digital consumption.