Abstract
Sorption of radionuclides on mineral surfaces strongly affects their fate and mobility in the geosphere. Therefore using of clay minerals as a barrier In LLW repositories can delay the dispersion of radionuclides into environment. That is of fundamental importance for maintaining environmental quality and for the safety and long-term performance of waste repositories.
In this study XRD analysis was applied to investigate three different types of clay minerals for quantitative analysis of each type and the MudMaster program for the measurement of the crystallite thickness distribution (CTD) according to of the BWA (Bertaut-Warren Averbach) technique. Six sample s of the three types of clay (Kaolin, Aswan clay and Ball clay) were studied. XRD and MudMaster were used to investigate the relation between CTD and Cs-137 uptake mechanism onto the clay. It was found that the best adsorption capacity related to the kaolinite content and the lowest CTD.