Scientists in the US have discovered a method to take carbon dioxide (CO2) from the air and make carbon nano fibres, a useful manufacturing material.
Their solar-powered system runs a small current via a tank full of a hot, molten salt; the fluid absorbs atmospheric CO2 and tiny carbon fibres slowly form at one of the electrodes.
It presently produces 10 grams per hour.
The team says it can be “scaled up” and will have an effect on CO2 emissions, however other researchers are uncertain.
Nonetheless, the method provides a much cheaper approach of creating carbon nano fibres than present strategies, according to Prof Stuart Licht of George Washington University.
“Till now, carbon nano fibres have been too expensive for many applications,” he informed journalists at the autumn meeting of the American Chemical Society in Boston.
Carbon nano fibres are already utilized in high-end applications such as electronic parts and batteries, and if prices came down they could possibly be used more extensively – enhancing the strong, light-weight carbon composites used in aircraft and automotive parts, for example.
The question is whether or not the “one-pot” reaction demonstrated by Prof Licht and his group could help to drop that price.
The thought of turning CO2 from the air into useful products is a popular one, and the field is strewn with many more unfulfilled promises than success stories.
However Prof Licht is confident his design can succeed. “It scales up very easily, the entire process is quite low energy.”
Daring vision
He additionally suggested that the system could provide “a reasonable path to bring down CO2 levels within the environment”.
This would involve adopting the reactors on a colossal scale and the concept has raised some eyebrows.
Dr Katy Armstrong, a chemical engineer at the University of Sheffield, stated the method was “promising and very fascinating on a lab scale” however that Prof Licht’s bigger vision could be problematic.
“As they’re capturing CO2 from the air, the method will need to cope with large volumes of gas to collect the required quantity of carbon, which could increase process costs when scaled up”
Dr Paul Fennell, a chemical engineer and clean energy researcher at Imperial College London, stated: “If they can make carbon nano fibres, that is a laudable aim and its a worthwhile product to have.
“But if your idea is to take CO2 out of the atmosphere and produce so many carbon nano fibres that you make a difference to climate change – I might be extremely surprised if you may do this.”
Prof Licht insists it’s worth attempting.
“There are no catches; there is a necessity to work collectively, to test this on a bigger scale, to use some societal resources to do that,” he said.
In the meantime, other chemists were impressed by fact that Prof Licht’s crew had produced nano fibres from atmospheric carbon.
