Flash method may allow quick recovery of precious metals from e-waste

A method called ‘flash Joule heating,’ which was originally developed to produce graphene from carbon sources like food waste, has been adapted by researchers at Rice University to recover rhodium, palladium, gold and silver from electronic waste.

In a report published in the journal Nature Communications, the scientists explain that the process uses up to 500 times less energy than current lab methods and since it removes highly toxic heavy metals including chromium, arsenic, cadmium, mercury and lead from the flashed materials, it also produces a byproduct clean enough for agricultural land.

Flash Joule heating consists of heating waste to 3,400 Kelvin (5,660 degrees Fahrenheit) with a jolt of electricity that vaporizes the precious metals contained in the feed. The gases are vented away for separation, storage or disposal.