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In the present study, a metal–organic framework ([Zn(bim)2(bdc)]n, MOF‐ZBB) compound was prepared and applied as an adsorbent for the removal of strontium ions from aqueous solutions. The influences of several variables such as pH, contact time, and temperature were studied in batch experiments. The effect of interfering cations (Ca2+, Mg2+, Na+, and K+) on the adsorption behavior was also investigated. The Freundlich, Langmuir, and Dubinin–Radushkevich isotherm models were used for the analysis of equilibrium data. The maximum adsorption capacity by applying the Langmuir equation was 123.451 mg g−1 at 75°C with a pH of 7. The thermodynamic study revealed that the adsorption process is endothermic and spontaneous. The results showed that the pseudo‐second‐order kinetic model for adsorption strontium ions onto MOF‐ZBB better described the adsorption process. Finally, the fixed‐bed column experiments were carried out at different feed flow rates to investigate the dynamic capacity of the adsorption process. The results revealed a decrease of about 80% in the efficiency of the column by increasing the flow rate from 1 to 4 ml min−1. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are porous network compounds that result from the reaction between a transition metal and organic ligands. In this work, cesium ions were removed by the use of a synthesized MOF, zinc benzimidazole benzene dicarboxylic acid [Zn(bim)2(bdc)]n (ZBB) in aqueous solution. Removal of cesium ions occurred with an ion-exchange mechanism. Scanning electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, Brunauer-Emmett-Teller, and thermogravimetric analysis were used to characterize ZBB complex. Bach technique was used for adsorption experiments and the effect of pH, time, temperature, and adsorbent dosage were studied. The study of adsorption isotherms indicated that the sorption process best fits Langmuir isotherm. Radiation studies indicated that this synthesized MOF could be used in medium-active wastewaters treatment. The column experiments were also investigated in order to obtain the dynamic capacity of the adsorption process. [ABSTRACT FROM AUTHOR]