The start of electric aviation is upon us, but it will take many more years before the average environmentalist can fly faultless on a full electric long-haul jet.
Meanwhile, scientists are trying to make the commercial aircraft we already have more sustainable, and one of the best ways to do that is to change the fuel they use.
Instead of spitting carbon dioxide (CO2) into the atmosphere, researchers at the University of Oxford and the University of Cambridge in the UK have now come up with a way for aircraft to capture this gas from the air and burn it for fuel.
Instead of creating a whole new fleet of electric aircraft, which will require major leaps in battery storage technology, this new approach will allow the world to reduce its carbon footprint from flying much faster. That is, if it turns out to work on a larger scale.
In the laboratory, researchers were able to capture and convert gaseous CO2 directly into aviation fuel using a cheap iron-based catalyst.
The amount of liquid fuel produced is still too small to operate an actual aircraft, but if fossil fuels can be captured from the air in high enough volume, converted to energy with sufficient efficiency and then sent out again, an aircraft can be theoretically carbon-neutral.
“This catalytic process provides an attractive route not only to reduce carbon dioxide emissions, but also to produce renewable and sustainable aviation fuel,”
“Recycling carbon dioxide as a carbon source for both fuel and high-quality chemicals offers significant potential for both the aerospace and petrochemical industries.”
When fossil fuels burn, the hydrocarbons they contain are converted into carbon dioxide and water, releasing energy. The new system essentially reverses this natural process.
By supplying the system with heat, engineers were able to combine carbon dioxide with hydrogen, separated from water, to produce a few grams of liquid fuel that the authors say could work in a jet engine.
The catalyst responsible for this impressive chemical reaction consists of iron, manganese and potassium, which are abundant in soil elements, easier and cheaper to prepare than many similar candidates. The catalyst also combines easily with hydrogen and shows high selectivity for a variety of jet fuel hydrocarbons.
The result is some fuel, in addition to several petrochemicals that can only be obtained from fossil fuels.
The new system is not the first, nor will it be the last to convert our carbon emissions into desirable biofuels. In Canada, researchers have developed a large industrial complex to capture CO2 like the trees in a forest, by using it to form hydrocarbon fuels.
But while a handful of studies have shown that it is possible to convert atmospheric CO2 In liquid fuels, it is extremely challenging and expensive to produce more than a small amount.
The new system looks promising, but whether it is practical is another matter.
“This looks different, and it looks like it might work,” said Joshua Heyne, an independent engineer who was not involved in the study. The cable.
“Upscaling is always a problem, and there are new surprises when you go to larger scales. But when it comes to a long-term solution, the idea of a circular carbon economy is definitely something that could be the future.”
Some, like Heyne, are hopeful, while others see “flying in the air” as just a hype. Last year, when a company in Europe announced that they were working on a way to capture CO2 from the air to power future aircraft, critics pointed out that the fuel produced each day would only allow five minutes of flight.
Such small crops are not a solution to the climate crisis, and some environmentalists claim that our only possible alternative is to fly less. Especially because the reality of a circular carbon economy is still far away and the crisis of climate change is already upon us.
In the end, it all depends on how fast we can scale up this promising technology, and the fact is that it may not happen fast enough.
Engineers will eventually connect the new system to established carbon emissions, such as coal-fired power plants, and this will of course require continued production of fossil fuels. It is also very expensive and may not appeal to businesses even if it worked.
Nevertheless, with climate change accelerating and aviation only increasing in the coming years, the CO engineering team claims2 conversion and utilization as “an integral and important part of greenhouse gas control and sustainable development.”
Other sustainable biofuels that depend on plants require large amounts of cultivated land and do not cope with our emissions at the same time.
“This is therefore the vision for the route to achieve net carbon emissions from aviation,” they conclude, “a turning point for a future global carbon-free aviation sector.”
The study was published in Nature communication.