Durán Avendaño, Yaneth StephanieCruz Hernández, NorgeRuiz Salvador, Ángel RabdelAbatal, Mohamed2025-07-042025-07-042025-04-27Durán Avendaño, Y.S., Cruz Hernández, N., Ruiz Salvador, Á.R. y Abatal, M. (2025). Further insight in the high selectivity of Pb2+ removal over Cd2 in natural and dealuminated rich-clinoptilolite. International Journal of Molecular Sciences, 26 (9), 4154. https://doi.org/10.3390/ijms26094154.1422-0067https://hdl.handle.net/11441/175011This research aims to understand the experimental results on the high selectivity of Pb2+ removal over Cd2+ in natural and dealuminated rich-clinoptilolite. For this purpose, we have considered the results of experimental and Density Functional Theory (DFT)-based simulated annealing (SA) on sorption of Pb2+ and Cd2+ from aqueous solution. The dealumination process of natural clinoptilolite (Nat-CLI) was done by H2SO4 solutions at different concentrations (0.1–1.0 M). The results show that the maximum sorption capacity (q,max) of Pb2+ and Cd2+ varied from 224.554 × 10−3 to 53.827 × 10−3 meq/g, and between 39.044 × 10−3 to 20.529 × 10−3 meq/g, respectively, when the values of Si/Al ratio change from 4.36 to 9.50. From a theoretical point of view, the global minimum energies of natural and dealuminated clinoptilolites before and after sorption of Pb2+ and Cd2+ were calculated by an SA method, where heating-cooling cycles were modeled by ab initio Molecular Dynamics followed by energy minimization. The theoretical results confirmed that for all Si/Al ratios, the sorption of Pb2+ and Cd2+ takes place, and for dealuminated systems, the exchange energy outcomes are more favorable for the Pb2+ cations. Since such energy differences are very small, it is not explained from a thermodynamic point of view. On the other hand, it could be understood from a kinetic perspective. In this way, we set that the atomic structural properties of the zeolite modify the first hydration coordination sphere of metal cations.application/pdf25 p.engAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/ClinoptiloliteDealuminationHeavy metalsIon-exchangeDFTSimulated annealinginfo:eu-repo/semantics/articleinfo:eu-repo/semantics/openAccesshttps://doi.org/10.3390/ijms26094154