A group of researchers in France say captured carbon dioxide can be used to extract metals from post-consumer electronics.
‘By simultaneously extracting metals by injecting CO2, you add value to a process that is known to be cost-intensive,’ says Julien Leclaire who leads the project at the University of Lyon. His team collected CO2 from a car exhaust, cooled it, then pumped it into a mix of chemicals called polyamines. The CO2 combined with the polyamines to create molecules of differing shapes and sizes.
This innovative process dissolves certain metals in the liquid while others become solid. Leclaire reports that his team successfully separated lanthanum, cobalt and nickel – all of which are used in batteries, computers and magnets.
If the process can be scaled up, it could be a more environmentally friendly way to recycle a range of e-scrap. An added benefit is that the CO2 method does not require highly reactive chemicals such as acids.
Leclaire notes that other researchers are currently trying to convert captured CO2 into plastics but this is chemically challenging. The process developed in Lyon is ‘more in line with how CO2 behaves naturally,’ he says. ‘Instead of mimicking what we know how to do better and cheaper with oil, let’s find things you can only do with CO2.’
The work has been published in the journal Nature Chemistry.