A team of researchers at the University of New South Wales has found a way to convert waste carbon dioxide into useful chemical compounds for industrial products- signaling a potential breakthrough in carbon recycling.
According to a release from UNSW, chemical engineers have developed a new way to convert carbon dioxide emissions into ‘building blocks’ that can be used to produce plastics and fuel.
“If adopted on a large scale” they explain, “process could give the world breathing space as it transitions toward a green economy.”
They have published their findings on a new technique to create nanoparticles that promote the conversion of carbon dioxide into industrial components online, which they say is much more affordable and scalable than what is currently available.
Dr Emma Lovell of UNSW’s School of Chemical Engineering explains that “we used an open flame, which burns at 2000 degrees, to create nanoparticles of zinc oxide that can then be used to convert CO2 using electricity, into syngas.”
“Syngas is often considered the chemical equivalent of Lego because the two building blocks – hydrogen and carbon monoxide – can be used in different ratios to make things like synthetic diesel, methanol, alcohol or plastics, which are very important industrial precursors.”
“So essentially what we’re doing is converting CO2 into these precursors that can be used to make all these vital industrial chemicals,” Lovell concluded.
Lovell’s colleague, Dr Rahman Daiyan explained that in the industrial context, waste carbon dioxide can be converted into useful permutations of syngas. “Waste CO2 from say, a power plant or cement factory, can be passed through this electrolyser, and inside we have our flame-sprayed zinc oxide material in the form of an electrode.”
“When we pass the waste CO2 in, it is processed using electricity and is released from an outlet as syngas in a mix of CO and hydrogen,” he said.
“At the moment you generate syngas by using natural gas – so from fossil fuels… but we’re using waste carbon dioxide and then converting it to syngas in a ratio depending on which industry you want to use it in,” he said.
A one to one ratio of carbon monoxide and hydrogen can be used to create fuel, while a four to one ratio of carbon monoxide and hydrogen can be used to create plastics.
The researchers say that the use of zinc oxide as the catalyst for the reaction is a cost-effective means of producing fuel and plastics.
“Past attempts have used expensive materials such as palladium, but this is the first instance where a very cheap and abundant material, mined locally in Australia, has been successfully applied to the problem of waste carbon dioxide conversion,” Dr Daiyan explained.
“It means it can be used industrially, it can be scaled, it’s super quick to make the materials and very effective,” he added. “We don’t need to worry about complicated synthesis techniques that use really expensive metals and precursors – we can burn it and in 10 minutes have these particles ready to go. By controlling how we burn it, we can control these ratios of desired syngas building blocks.”
Dr Lovell explained the team’s plans on expanding the experiment to show how it could be applied to something the size of a power plant. “The idea is that we can take a point source of CO2, such as a coal fired power plant, a gas power plant, or even a natural gas mine where you can liberate a huge amount of pure CO2 and we can essentially retrofit this technology at the back end of these plants.”
“Then, you could capture that produced CO2 and convert it into something that is hugely valuable to industry,” she said.