Ellen Phiddian
A team of US and Malaysian scientists has found a process that can both capture CO2 from flue gas and convert it into another material.
They believe the process could be useful in preventing carbon emissions from hard-to-abate sectors like concrete or steel-making.
Typical carbon capture and use projects capture carbon dioxide in one step, and convert it to something else in another. Both processes are usually energy and resource intensive.
This research, described in ACS Catalysis, demonstrates that the two processes can be combined, and sheds some light on how the reaction works.
While still highly experimental, the researchers believe the process could one day help to make devices that dramatically improve conventional carbon capture from industrial. It’s unlikely to be powerful enough to capture CO2 from the air alone.
Conventional carbon capture technology often involves a solution of chemicals called amines, through which flue gas from industrial processes is pumped.
Carbon dioxide sticks to the amines and then is extracted via heat and either buried underground or converted into something else.
This team of researchers had previously seen success with putting an electrode in the amine solution. This helps to turn the CO2 into solid carbonate, which can then be used for other things.
In this study, the researchers figured out what dictated the bicarbonate reaction. They found the “active species” – the thing that prompted the reaction – was carbon dioxide.
“This is not a removal technology, and it’s important to state that,” says Associate Professor Betar Gallant, a researcher at Massachusetts Institute of Technology, US.
“The value that it does bring is that it allows us to recycle carbon dioxide some number of times while sustaining existing industrial processes, for fewer associated emissions.
“Ultimately, my dream is that electrochemical systems can be used to facilitate mineralisation, and permanent storage of CO2 — a true removal technology. That’s a longer-term vision.”
