Metals from e-waste recycled more sustainably

The team was led by Rice University’s James Tour, the T.T. and W.F. Chao Professor of Chemistry and professor of materials science and nanoengineering. Their findings are detailed in Nature Chemical Engineering.

“Our process offers significant reductions in operational costs and greenhouse gas emissions, making it a pivotal advancement in sustainable recycling,” Tour said in a statement.

The new technique enhances the recovery of critical metals and builds on Tour’s earlier work in waste disposal using flash Joule heating (FJH). This process involves passing an electric current through a material to rapidly heat it to extremely high temperatures, transforming it into different substances.

The researchers applied FJH chlorination and carbochlorination processes to extract metals including gallium, indium and tantalum, from e-waste. Traditional recycling methods such as hydrometallurgy and pyrometallurgy are energy-intensive, produce harmful waste streams and involve large amounts of acid.

In contrast, the new method eliminates these challenges by enabling precise temperature control and rapid metal separation without using water, acids or other solvents.