New catalyst for recycling carbon dioxide discovered
Imagine if we could take CO2, that most notorious of greenhouse gases, and convert it into something useful. Something like plastic, for example. The positive effects could be dramatic, both diverting CO2 from the atmosphere and reducing the need for fossil fuels to make products.
A group of researchers, led by the University of Toronto Ted Sargent group, just published results that bring this possibility a lot closer.
Using the Canadian Light Source and a new technique exclusive to the facility, they were able to pinpoint the conditions that convert CO2 to ethylene most efficiently. Ethylene, in turn, is used to make polyethylene—the most common plastic used today—whose annual global production is around 80 million tonnes.
“This experiment could not have been performed anywhere else in the world, and we are thrilled with the results” says U of T PhD student Phil De Luna, the lead researcher on this project.
At the heart of this work is the carbon dioxide reduction reaction, wherein CO2 is converted into other chemicals through the use of an electrical current and a chemical reaction, aided by a catalyst.
Many metals can serve as catalysts in this type of reaction: gold, silver and zinc can make carbon monoxide, while tin and paladium can make formate. Only copper can produce ethylene, the core component of polyethylene plastic.
“Copper is a bit of a magic metal. It’s magic because it can make many different chemicals, like methane, ethylene, and ethanol, but controlling what it makes is difficult,” says De Luna.
That is precisely what the team’s results address, however. They were able to design a catalyst and pinpoint the ideal conditions to maximize ethylene production, while minimizing the methane output to nearly nothing.
Paired with carbon capture technology, this could lead to an incredibly green production mechanism for everyday plastics, meanwhile sequestering harmful greenhouse gases.