A review of CO2 removal technologies for a sustainable future.

Carbon dioxide (CO2) is a major pollutant in both indoor and outdoor environments, posing significant health risks and contributing to environmental degradation and climate change. This review highlights recent advancements in air purification and CO2 control technologies. A comprehensive assessment of adsorption, catalytic oxidation, photocatalysis, biofiltration, and membrane separation technologies is presented, with emphasis on their mechanisms, materials, and performance characteristics. In addition, the review examines current large-scale CO2 removal and deployment strategies, including direct air capture, carbon capture and storage, bioenergy with carbon capture and storage, and industrial-scale adsorption and membrane systems. Key challenges limiting widespread implementation, such as material constraints, energy requirements, process scalability, and economic feasibility, are critically discussed. The potential of hybrid systems and emerging technologies, including artificial intelligence-based process optimization, is also evaluated for improving efficiency and sustainability. Finally, future research directions and policy recommendations are proposed to overcome existing barriers and accelerate the large-scale adoption of CO2 mitigation technologies.