Dostie et al. (2025): Carbon dioxide supply and scaling constraints on direct air capture using calcium oxide powder
Lance Dostie, Ian M. Power, Kwon Rausis, IN: Journal of Cleaner Production, https://doi.org/10.1016/j.jclepro.2025.146635
Calcium oxide (CaO; lime) looping is a carbon dioxide (CO₂) removal technology that can mitigate carbon emissions. However, scaling this technology requires a thorough understanding of the rate-limiting effects of CO₂ supply on CO₂ removal rates at and below atmospheric CO₂ concentration levels, as well as with various CaO thicknesses and plot areas. Here, the authors show that carbonation is readily limited by CO₂ supply even under high flow rates (e.g., 25 mmol CO₂/h over 100 g CaO). Subsequently, the CO₂ capture efficiencies using CaO and Ca(OH)₂ powders were investigated under ambient CO₂ concentrations (397–490 ppm) to 100 ppm.