Caltech’s new CO2 recycler could be a game-changer for space exploration

How do science fiction movies get away with not having their A-list actors spend the whole time wearing bulky space suits on far-off planets? Simple: They use the trope of terraforming or oxygen generators to explain how it’s possible to walk around on inhospitable planets without a problem. Unfortunately, achieving this in real life is a whole lot more difficult.

But thanks to researchers at the California Institute of Technology (Caltech), it may not remain that way forever. Caltech researchers have developed a special reactor that can transform carbon dioxide into molecular oxygen. This could prove to be a potential game-changer for generating oxygen in space.

“Carbon dioxide is a very stable molecule with strong chemical bonds, the main reason why it is extraordinarily difficult to remove reactively from Earth’s atmosphere,” Konstantinos Giapis, professor of chemical engineering, told Digital Trends. “We have developed a way to use kinetic energy to bring the carbon dioxide molecule to its breaking point. This in itself would be unremarkable, as there are other ways to do it with expected results. However, we have discovered that we can twist and bend those sturdy chemical bonds to bring the two oxygen atoms together, close enough to force the carbon dioxide molecule to disintegrate spontaneously, releasing molecular oxygen. This is an unexpected, indeed unfathomable response of the molecule: A true exotic reaction.”

This discovery could have profound implications in a number of areas. Kinetic energy-driven reactions open up new ways to do chemistry with small molecules. In astrophysics, it could help explain the origin of trace amounts of molecular oxygen found in the upper atmosphere of Mars, as well as on early Earth before the onset of primitive life-forms. But perhaps the most exciting application involves potential space travel to Mars.

“Although we have used a large, complex, and heavy reactor to study and prove the reaction, other simpler devices are possible which will produce more oxygen than in the current study,” Giapis said. “We have designed and applied for a patent on a lightweight ‘mug-size’ plasma reactor, which can operate in the low-pressure atmosphere of Mars, possibly serving as an oxygenator device for astronauts strolling its surface.”

Going forward, Giapis said the team aims to optimize a portable plasma device for producing breathable oxygen in a simulated martian atmosphere. They also aim to find ways to carry out more efficient ionization to improve the yield of molecular oxygen.

A paper describing the work was recently published in the journal Nature Communications.