An international team of researchers has developed a method for producing jet fuel using atmospheric carbon dioxide.
This new technology allows - if proven to be widely usable - to reduce the carbon emissions from aviation in a short time.
The researchers presented this innovative technology in their recently published paper in Nature Communications, and a report by ScienceAlert reported its most important findings.
Carbon gas from the atmosphere
As they continue to search for ways to reduce the amount of carbon dioxide emitted into the atmosphere, scientists are increasingly focusing on sectors that pollute the most.
One of these sectors is air transport, which is the source of around 12% of the CO2 emissions associated with transportation, which contribute about 3% to global warming resulting from human activity.
Reducing carbon emissions in this area has proven to be a challenge due to the difficulty of using clean energies and installing heavy batteries inside aircraft.
In this new study, an international team of researchers led by the University of Oxford developed a chemical process that can be used to produce carbon-free fuels.
Instead of blowing carbon dioxide into the atmosphere, planes will be able to capture this gas from the air and burn it as fuel.
The researchers used a process called the organic combustion method to convert carbon dioxide in the air into jet fuel and other products.
Normally, when fossil fuels are burned, the hydrocarbons they contain turn into carbon dioxide and water, which releases energy.
But the new process turns this natural process on its head.
The new fuel could transform the air transport sector into an environmentally clean sector (Paxhair)
Carbon gas as energy
Researchers have been able to combine carbon dioxide (CO2) and hydrogen (hydrogen) at a temperature of 350 degrees Celsius to produce a few grams of liquid fuel that they say can work in a jet engine.
The catalyst responsible for this impressive chemical reaction is composed of iron, manganese, and potassium, which are abundant earth elements, easier to prepare and cheaper than many similar elements.
It also reacts easily with hydrogen, and shows a high selectivity to a group of jet fuel hydrocarbons.
The process produces the type of hydrocarbon molecules that make up liquid jet fuel, as well as the formation of water molecules and other products.
Testing showed that, within 20 hours, the process converted 38% of the carbon dioxide in a pressurized chamber into jet fuel and other products.
Jet fuel accounted for 48% of them.
The rest of the products were water, polypropylene, and ethylene.
The researchers also noted that using this fuel in aircraft would be "carbon neutral" because burning it would release the same amount of carbon dioxide that was used to make it.
The researchers say their process is less expensive than other methods used to produce jet fuel, such as those that convert hydrogen and water into fuel, because they use less energy.
They also indicated that innovative conversion systems could be installed in plants that currently emit large amounts of carbon dioxide, such as coal-fired power plants.
Promising method
This new system, which turns carbon emissions into biofuels, is not the first of its kind.
In Canada, scientists set up a few years ago an industrial complex to capture carbon dioxide gas like trees, to be used in the manufacture of hydrocarbon fuels.
Researchers from Boston University were able in 2015 to develop a similar technique by capturing carbon gas from the atmosphere and converting it into nanotubes using lithium-oxide and solar energy to reach temperatures of 750 degrees Celsius.
The amount of liquid fuel produced in the new study is still far too small to operate an actual aircraft, but the study's authors say this process reveals a promising way not only to reduce carbon dioxide emissions, but also to produce renewable and sustainable jet fuel.
That is if carbon could be captured from the air in sufficient quantities and converted into energy efficiently.