Adsorption mechanism of carbonated cement in geological disposal environments for cobalt

CO 2 may erode cement structure of geological disposal repository in the long-term disposal process. This study investigates the adsorption behavior and mechanism of carbonated cement for Co 2+ via characterization and adsorption experiments. Characterization experiments show that the carbonation does not change the adsorption mechanism of cement for Co 2+ . Adsorption experiments show that carbonation reduces the adsorption capacity of cement. In general, the adsorption of Co 2+ by both pristine and carbonated cement involves multiple mechanisms including ion exchange and chemical adsorption. This study provides critical data for safety assessments of the geological disposal repository.