Researchers from Australia have successfully turned carbon dioxide back into coal in a bid to prevent further catastrophe caused by global warming.
The team led by RMIT University in Melbourne proposed that converting the greenhouse gas into a solid form addresses the environmental and economic concerns as well as fear of possible leaks from storage of recaptured CO2. They believe that their technique provides a safe and permanent option to remove greenhouse gases from the atmosphere.
“While we can’t literally turn back time, turning carbon dioxide back into coal and burying it back in the ground is a bit like rewinding the emissions clock,” stated Torben Daeneke, a researcher from RMIT University and an Australian Research Council DECRA Fellow.
Previous research used solid metal catalysts, which increases the rate of chemical reaction, to convert recaptured CO2 into coal. While effective, the technique comes with a lot of issues.
For one, it requires temperature above 600 degrees Celsius in order to convert the greenhouse gas into a solid form. It would take a whole lot of energy and, therefore, a whole lot of money, to provide the extreme heat needed to kickstart the process.
A solid metal catalyst also tends to gam up very quickly, decreasing its ability to keep a chemical reaction going.
However, the new technique proposed in a paper published in the journal Nature Chemistry uses liquid metal catalysts which, the researchers claim, stay liquid at room temperature. They converted CO2 by dissolving the greenhouse gas into a beaker filled with a small amount of liquid metal and electrolyte liquid which is then charged using an electrical current.
The process slowly converts the recaptured CO2 into solid flakes of carbon that naturally detaches from the liquid metal catalyst.
Dorna Esrafilzadeh, the lead author of the study, said that the new technique offers many other benefits.
“A side benefit of the process is that the carbon can hold electrical charge, becoming a supercapacitor, so it could potentially be used as a component in future vehicles,” the researcher claimed. “The process also produces synthetic fuel as a by-product, which could also have industrial applications.”
The team admitted that more research is needed before the new technique is used to convert and store CO2. However, Esrafilzadeh believes that their work is the first step to deliver greenhouse gas into its solid form and address global warming.