Direct Air Capture of Carbon Dioxide into MFI Frameworks by Low‐Temperature Swing Under Realistic Humidity

The urgent need to combat global warming inspired the introduction of the concept of carbon dioxide direct air capture (CO₂-DAC), a key strategy for decentralized greenhouse gas removal from air. In this study, a simple approach for CO₂-DAC is introduced, utilizing ZSM-5 and its ion-exchanged analogues to effectively concentrate CO₂ from humid air (80% RH) at 5 °C and enable its recovery at a moderate desorption temperature of 25 °C where in both cases, ambient air served as a sustainable CO₂ source and desorption medium. Repeated adsorption (5 °C) and desorption (25 °C) cycles confirm the adsorbent stability under realistic conditions. Based on Monte Carlo (MC) and molecular dynamics (MD) simulations, a preferential CO₂ adsorption via electrostatic interactions with minimal competitive adsorption with H₂O is observed, explained by the facile diffusion of CO₂ into the micropores compared to the preferred H₂O adsorption on the outer surface of the zeolite. These experimental and theoretical insights pave the way for industrial CO₂-DAC applications using zeolite-based adsorbents.