New method pulls CO2 from air using cold air, simple sorbents

Researchers at Georgia Tech have developed a novel, cost-effective method for capturing atmospheric CO₂ by leveraging extremely cold air and simple, widely available porous sorbent materials called physisorbents. Their technique utilizes the cold energy generated during liquefied natural gas (LNG) regasification—a process that typically wastes this cold—to chill ambient air to near-cryogenic temperatures (~ -78°C). This cooling removes water vapor naturally, creating ideal conditions for physisorbents like Zeolite 13X and CALF-20 to efficiently absorb CO₂ without the energy-intensive drying steps required by traditional direct air capture (DAC) systems that rely on chemical amines. The physisorbents demonstrated roughly three times higher CO₂ capture capacity at these low temperatures compared to room temperature, while also requiring less energy for CO₂ release and offering greater durability. Economic modeling indicates this approach could reduce DAC costs to around $70 per metric ton of CO₂—less than one-third of current expenses—potential