Arraga et al. (2026): Demonstration of direct air capture of CO₂ using microalgae raceway reactors
R. Arraga, M. Barceló-Villalobos, R. Esteitie, M. Ahaddouch, C. Sánchez-Salinas, F.G. Acién, IN: Journal of CO₂ Utilization, https://doi.org/10.1016/j.jcou.2026.103376
The continuous increase in atmospheric CO₂ concentration underscores the urgent need for scalable and energy-efficient carbon removal technologies. This study demonstrates, for the first time, the implementation of a tailored Direct Air Capture (DAC) concept integrated within large-scale microalgae raceway reactors, enabling direct CO₂ uptake from ambient air without external gas supply. A 600 m² reactor operated continuously with Scenedesmus sp. maintained stable productivity (12 g m⁻² day⁻¹) under extreme carbon limitation (TIC ≈ 20 mg L⁻¹, pH ≈ 10).