“Flash heating” aims to reduce costs and greenhouse gas emissions.
The demand for critical minerals for green and digital technologies is growing, while their availability is limited, and production is often concentrated in a few countries. Recycling is becoming increasingly important to secure supply and reduce both import dependency and the need for new mining projects. A research team from Rice University in Texas has now developed a method to recover metals from electronic waste more efficiently and environmentally friendly. According to the university’s press release, many conventional recycling methods are energy-intensive or require the use of acids, leaving behind dangerous waste products. The new method, however, relies on precise temperature control and rapid metal separation without using water, acids, or other solvents.
It builds on previous work (we reported) by scientists James Tour and Bing Deng on waste processing using Flash Joule Heating. In this process, electrical current is passed through a material, heating it to extremely high temperatures of over 2,000 degrees Celsius within a short time, transforming it into various substances. According to the researchers, this technique successfully separated metals like tantalum from capacitors, gallium from LEDs, and indium from solar film. By precisely controlling reaction conditions, they achieved metal purity levels of over 95% and yields of more than 85%. The process could significantly reduce operating costs and greenhouse gas emissions, explains Tour.
Next, the method will be adapted to recover other critical metals from waste streams. The researchers believe it could also be suitable for extracting lithium and rare earth elements essential for energy and transportation transitions.
Photo: iStock/WhiteBarbie
