Scientists Find a Cheaper and Easier Way to Pull CO₂ from the Air
Removing carbon dioxide directly from the atmosphere has long been one of the holy grails of climate science. Researchers at the University of Helsinki have developed a new method that could make it far more practical and affordable than anything we have today, according to a study published in the journal Environmental, Science and Technology.
The new approach, developed by postdoctoral researcher Zahra Eshaghi Gorji, uses a specially designed chemical compound to act like a sponge for CO₂. Pour it into the air and it soaks up carbon dioxide while ignoring everything else; nitrogen, oxygen, and other gases simply pass right through.
The numbers are impressive: just one gram of the compound can absorb 156 milligrams of CO₂ straight from normal, unfiltered air. That already beats the performance of existing carbon capture technologies.
Capturing CO₂ is only half the challenge. You also need to be able to release it cleanly so it can be stored or reused and that’s where most current methods fall short. Today’s carbon capture compounds typically need to be heated to above 900°C to release the CO₂ they’ve absorbed. That requires enormous amounts of energy and makes the whole process expensive. This new compound releases its CO₂ at just 70°C in around 30 minutes, roughly the temperature of a hot cup of tea. The result is clean, reusable CO₂ with a fraction of the energy cost.
The compound doesn’t wear out quickly either. After 50 cycles of absorbing and releasing CO₂, it retained 75% of its original capacity. After 100 cycles, it still held 50%. For an industrial process, that kind of durability matters enormously.
The compound was found after more than a year of experiments testing different chemical combinations. The winning formula combines a base called TBN (developed by a separate research group at the university) with benzyl alcohol. “None of the components is expensive to produce,” said Eshaghi Gorji. On top of that, the liquid is non-toxic, which removes a major safety concern that dogs many industrial chemical processes.
The team is now preparing to scale things up from laboratory grams to pilot-plant quantities. To do that, the liquid compound needs to be converted into a solid form. “The idea is to bind the compound to compounds such as silica and graphene oxide, which promotes the interaction with carbon dioxide,” explained Eshaghi Gorji.
If the pilot tests go well, this could be a significant step towards carbon capture technology that is actually practical to deploy at scale, something the world urgently needs as it looks for ways to rein in rising CO₂ levels.
Zahra Eshaghi Gorji, Baljeet Singh, Antti Lempinen, and Timo Repo. Direct Air Capture: Recyclability and Exceptional CO2 Uptake Using a Superbase. Environmental Science & Technology 2025 59 (49), 26506-26513, DOI: 10.1021/acs.est.5c13908