Synthesis of a novel magnetic zeolite nanocomposite for removal of Cs+ and Sr2+ from aqueous solution: Kinetic, equilibrium, and thermodynamic studies

In this study, a novel magnetic zeolite nanocomposite (MZNC) was prepared by nanozeolite A and iron oxide. Nanocrystalline zeolite A was synthesized, and then, iron oxide nanocrystals were prepared in the presence of nanozeolite. The prepared nanocomposite was characterized by XRD, XRF, FT-IR, DTG, VSM, and TEM methods. The applicability of the synthesized nanocomposite for removal of Cs+ and Sr2+ from aqueous solutions was assessed, and the effective parameters such as initial concentration, initial pH, contact time, and temperature on the sorption process were studied and optimized. The composite was able to remove 95.2% and 81.4% of Sr+2 and Cs+1 from 0.01 N aqueous solutions, respectively. The kinetic studies showed that the process was quite rapid, and 90% of equilibrium capacity was achieved within 30 min. Experimental kinetic data were found to be well fitted with pseudo-second-order kinetic model with rate constant of 0.2845 and 0.2722 g mmol−1 min−1 for Cs+ and Sr2+, respectively. The Langmuir, Freundlich, and D–R isotherm models were used to describe the equilibrium data. The saturation magnetization of nanocomposite was measured as 19.50 emu g−1, which facilitated magnetic separation of the sample after adsorption process.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (67 K)Download as PowerPoint slideHighlights► A novel magnetic zeolite A nanocomposite was synthesized and characterized. ► Synthesis was performed through a new two sequential steps method. ► The nanocomposite was separated efficiently by fast and simple magnetic separation. ► It showed higher sorption capacity for Cs+ and Sr2+ than microzeolite composite. ► The adsorption process onto nanocomposite was kinetically very fast.