See more from this Division: Joint Sessions
See more from this Session: Natural Zeolite Utilization in Agriculture, Environmental Science, and Industry: Characterization, Properties, and Applications
Abstract:
In this study, ternary and quaternary ion-exchange experiments involving the cations Na+, K+, Cs+, Sr2+, and Ca2+ and the zeolite mineral clinoptilolite were conducted. In the ternary ion-exchange experiments, homoionic forms of Na+-, K+-, and Ca2+-clinoptilolite prepared from Death Valley Junction, California, clinoptilolite-rich tuff were reacted with solution mixtures of Na++K++Cs+, Na++K++Sr2+, and Na++K++Ca2+ at constant solution normality. The quaternary ion-exchange experiment studied a Na++K++Ca2++Sr2+system.
The ion-exchange equilibria were modeled using a thermodynamic approach based on the Wilson equation. Published ion-exchange data were used to derive the Wilson equation parameters and the equilibrium constants for binary ion exchange. A correlation method that has been applied to predictions of formation constants of aqueous hydroxo-metal complexes was used to help constrain the equilibrium constants. The Wilson model, with parameters derived only from binary ion-exchange data, was used to predict ternary and quaternary ion-exchange equilibria. A comparison of experimental data for ternary and quaternary systems and thermodynamic model predictions indicates that the Wilson model adequately reproduces multicomponent ion-exchange equilibria.
This study was funded by the Southwest Research Institute® Internal Research and Development Project 209211.
See more from this Division: Joint Sessions
See more from this Session: Natural Zeolite Utilization in Agriculture, Environmental Science, and Industry: Characterization, Properties, and Applications