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Alkaline earth metals, such as calcium and magnesium oxides, readily react with carbon dioxide (CO₂) to produce stable carbonate minerals. Carbon sequestration through the formation of carbonate minerals is a potential means to reduce CO₂ emissions. Calcium-rich, industrial solid wastes and residues provide a potential source of highly reactive oxides, without the need for pre-processing. This paper presents the first study examining the feasibility of carbon sequestration in cement kiln dust (CKD), a byproduct generated during the manufacturing of cement. A series of column experiments were conducted on segments of intact core taken from landfilled CKD. Based on stoichiometry and measured consumption of CO₂ during the experiments, degrees of carbonation greater than 70% of the material's potential theoretical extent were achieved under ambient temperature and pressure conditions. The overall …