Influencing factors of 90Sr adsorption onto granite fracture filling material in a high-level radioactive waste disposal site

A granite fracture filling material (FFM) collected from a candidate high-level radioactive waste (HLRW) geological disposal was used to evaluate the sorption behavior of 90 Sr. The sorption process was fitted with the Henry and Freundlich models, and the distribution coefficient ( K d ) values ranged between 117.4 and 434.8 mL/g, according to the batch experimental results. Furthermore, the K d value and sorption percentage were affected by the initial solution specific activity, pH, FFM particle size, bicarbonate ion content and solid-to-liquid ratio. This work provides important information for the geological barrier of the repository. Article highlights A granite fracture filling material sample collected from a HLRW geological disposal. The sorption process was fitted using the isotherm models of Henry and Freundlich. The main factors affecting the sorption of 90 Sr were discussed.