It has become difficult to prevent global warming at a level that reduces carbon dioxide (CO₂) emissions. As the speed of climate change accelerates, the world is now focusing on technologies that directly remove the carbon dioxide already emitted into the atmosphere. Researchers in Korea have developed a dream technology that can separate carbon dioxide from the air and recycle it as a chemical raw material, the first of its kind in the world. The electricity required is sufficient to charge a smartphone.
Professor Go Dong-yeon of the Korea Advanced Institute of Science and Technology (KAIST) noted in a phone interview on the 27th that "the technology for capturing carbon dioxide from the atmosphere applied for a patent in 2022 and has recently completed verification, and it is expected that commercialization will be possible within three years if manufacturing facilities and personnel needed are secured."
Direct air capture (DAC) technology is a method that directly separates carbon dioxide dispersed in the air. As analysis shows that it is difficult to prevent global warming through efforts to reduce greenhouse gas emissions alone, this technology is emerging as an alternative.
The problem is that the concentration of carbon dioxide in the air is only several hundred ppm (1 ppm is one part per million). To capture the necessary amount of carbon dioxide, a large volume of air must be processed, and to remove the captured carbon dioxide from the capture device, it had to be heated to 100 degrees Celsius. More than 70% of the total energy was consumed in this process.
To solve this problem, Professor Go applied the principle of a hairdryer. By flowing electric current through a filter that captures carbon dioxide to heat it, carbon dioxide can be easily separated without the need for hot steam or complicated equipment as before. It can operate with just a 3V voltage suitable for charging a smartphone. It can also be integrated with renewable energy sources like solar and wind power.
He said, "The key to this technology is rapidly heating the filter to 110 degrees in just 80 seconds with only 3V of low power," adding that "the process of capturing and then separating carbon dioxide is much faster, and unnecessary heat loss has been reduced by about 20% compared to before."
Professor Go recently revealed that he verified the technology developed this time through simulations conducted at the Massachusetts Institute of Technology (MIT). This research achievement was published in the international journal "Advanced Materials" on the 1st. It was recognized for its excellence and was also selected for the internal cover.
The research team developed a fiber-type filter that is one-fifteenth the thickness of a human hair. They put an adsorbent, which effectively captures carbon dioxide, into this filter and coated the surface with silver nanoparticles, allowing it to generate heat when electric current flows. The filter created in this way allows for efficient capture, as it conducts electricity well while enabling carbon dioxide to move uniformly and quickly warm the interior.
The carbon dioxide captured from the air can be buried or recycled as a chemical raw material if its concentration is raised to 95%. Professor Go explained, "The concentration of carbon dioxide in the air is only 0.04%, but raising it to 95% meets the minimum requirements necessary for underground storage or use as a chemical raw material," adding that "the higher the purity, the better the efficiency of recycling and transportation."
This technology can operate continuously, meaning it can keep running from the time it is installed until it breaks down, and the lifespan of the adsorbent is between one to one and a half years, at which point it can be replaced if necessary.
Professor Go is promoting the commercialization of the technology through "Sorv," a company he co-founded with KAIST colleagues in 2023. For commercialization, it is necessary to connect modules, the basic units of the capture devices, in a wide area. Professor Go stated, "If the conditions for mass-producing modules are met, commercialization can be achieved within three years," adding that "the key is securing at least 20 production facility and manufacturing personnel."
Professor Go is also working on domesticating DAC core technology within a consortium supported by the Ministry of Science and ICT since 2023. He said, "While the DAC developed this time was born as domestic core technology, the more diverse the core technologies are secured, the higher their applicability."