Kinetics and Rietveld XRD structural study of Cs+ sorption on natural and synthetic mordenites in the first 12 h

Kinetics of Cs+ uptake by natural and synthetic mordenites was studied. The experimental data is best fitted to the pseudo-second-order rate model and the parameters k(2) and q(e) are calculated. The application of intra-particle diffusion and liquid film diffusion models show multilinear graphical dependence, indicating that both mechanisms influence the run of uptake. Rietveld XRD structural analyses were used for identification of the positions preferably occupied by Cs+ cations during the ion-exchange as a function of contact time. The obtained results show that the predominance of Na+ ions in the initial samples makes the exchanged sites more accessible by Cs+ ions.

Automated summary

The kinetics of Cs+ uptake by natural and synthetic mordenites was studied in this research. The experimental data was best fitted to the pseudo-second-order rate model, indicating that both intra-particle diffusion and liquid film diffusion mechanisms influenced the uptake process. Rietveld XRD structural analysis revealed the preferred positions occupied by Cs+ cations during ion-exchange, with the presence of Na+ ions in the initial samples making the exchange sites more accessible to Cs+ ions.