Sorption kinetics of cesium on natural mordenite

The characteristics of sorption kinetics of cesium on natural mordenite, including apparent rate constant, intraparticle diffusion coefficient and reaction mechanisms, were investigated in this study. The apparent rate constant of sorption, as derived from the semi-empirical Elovich equation, was indicated from the experimental results to be about 56.9 μequiv·g^-1·s^-1. The rate-determining step of sorption reaction was identified as the intraparticle diffusion of cesium cation from the main channel to site B, which is located in the side void, through the side channel system of mordenite. The linear and nonlinear intraparticle diffusion coefficients of Cs⁺ were observed via calculation by the spherical diffusion model as being 4.7 × 10^-18 and 3.5 × 10^-18m²·s^-1, respectively.