Evaluation of Sorption Distribution Coefficient of Cs onto Granite using Sorption Data Collected in Sorption Database and Sorption Model

Abstract

Based on the sorption distribution coefficients (K_d) of Cs onto granite collected from the JAERI Sorption Database (SDB), the parameters for a two-site model without the triple-layer structure were optimized. Comparing the experimentally measured Kd values of Cs onto Mizunami granite carried out by JAEA with the K_d values predicted by the model,the effect of the ionic strength on the K_d values of Cs onto granite was evaluated. It was found that K_d values could be determined using the content of biotite in granite at a sodium concentration([Na]) of 1 x 10^-2 to 5 x 10^-1 mol/dm³. It was suggested that in high ionic strength solutions, the sorption of Cs onto other minerals such as microcline should also be taken into account.