The new technology captures CO2 locks it into a solid state to keep it from escaping into the atmosphere.
Decarbonization poses great challenges for energy-intensive heavy industries like cement and steel production, which each contributes about 7% of total global CO2 emissions. And as the two sectors will continue to grow in coming years and decades, reducing their carbon footprints is a must.
Encouragingly, in an effort to help heavy industries decarbonize a team of Australian researchers has just come up with an efficient new way of capturing carbon dioxide before it is released and converting it to solid carbon.
The new technology captures CO2 as it is produced and locks it into a solid state to keep it from escaping into the atmosphere in gas form.
“Our new method harnesses the power of liquid metals, but the design has been modified for smoother integration into standard industrial processes,” explains Torben Daeneke, an associate professor at RMIT University in Melbourne.
“Turning CO2 into a solid avoids potential issues of leakage and locks it away securely and indefinitely,” he says. “And because our process does not use very high temperatures, it would be feasible to power the reaction with renewable energy.”
Better yet: the process is simple enough to be scaled up to industrial levels.
“[T]he new tech is radically more efficient and can break down CO2 to carbon in an instant. We hope this could be a significant new tool in the push towards decarbonisation, to help industries and governments deliver on their climate commitments and bring us radically closer to net zero,” Daeneke said.
To develop their new technology the researchers relied on already widely used thermal chemistry methods. During their process liquid metal is heated to 100C-120C and then carbon dioxide is injected into it with bubbles of the gas rising up in the liquid metal similarly to the way bubbles do in a fizzy drink.
As the bubbles move through the liquid metal, the gas molecule splits up to form flakes of solid carbon in a reaction that takes a split second, which is what makes the process very efficient.
“It’s the extraordinary speed of the chemical reaction we have achieved that makes our technology commercially viable, where so many alternative approaches have struggled,” notes Ken Chiang, a member of the research team.
The team is also working on new solutions to use the solid carbon derived from their process in construction materials and useful other ways.
“Ideally the carbon we make could be turned into a value-added product, contributing to the circular economy and enabling the CCS technology to pay for itself over time,” Daeneke says.