Scientists from RMIT University have discovered an economically viable process of converting carbon dioxide into solid coal through liquid metals.
Current methods for carbon capture and storage involve converting carbon dioxide into a liquid form that has concerns with the environment such as leaks from the storage sites.
Their study was published in the journal Nature Communications that provides a safer method of carbon dioxide removal from the atmosphere.
One of the researchers Dr. Torben Daeneke said that it is more sustainable to convert carbon dioxide into coal.
"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," Daeneke, an Australian Research Council DECRA Fellow, said.
"To date, CO2 has only been converted into a solid at extremely high temperatures, making it industrially unviable.
"By using liquid metals as a catalyst, we've shown it's possible to turn the gas back into carbon at room temperature, in a process that's efficient and scalable.
"While more research needs to be done, it's a crucial first step to delivering solid storage of carbon."
How carbon dioxide is converted into coal
The main proponent Dr. Donna Esrafilzadeh, a Vice-Chancellor's Research Fellow in RMIT's School of Engineering, devised the method in carbon dioxide capture and storage through an electrochemical technique.
The team developed a liquid metal catalyst that converted carbon dioxide. This catalyst has specific surface properties and is efficient at electrical conduction.
A small amount of liquid metal and an electrolyte liquid is placed in a beaker and dissolves the carbon dioxide. This carbon dioxide is then subjected to electricity.
Carbon dioxide is then slowly converted into carbonaceous solid and could also be used as an electrode.
"A side benefit of the process is that the carbon can hold an electrical charge, becoming a supercapacitor, so it could potentially be used as a component in future vehicles."
"The process also produces synthetic fuel as a by-product, which could also have industrial applications."
