Synthesis of functionalized porous montmorillonite via solid-state NaOH treatment for efficient removal of cesium and strontium ions uri icon

abstract

  • Solid-state NaOH treatment of montmorillonite clay was used to enhance the removal of Cs+ and Sr2+. Through this facile and low-cost modification, montmorillonite with a large BET surface area (117.1m2 g1) and many surface functional groups (SiONa), demonstrated enhanced sorption kinetics (89% removal for 40mg L1 Cs+ and 23mg L1 Sr2+ in 1h) with a sorption capacity of 290.7mgg1 for Cs+ and 184.8mgg1 for Sr2+, greatly exceeding the low sorption capacity (137.0mgg1 for Cs+ and 15.6mgg1 for Sr2+) of pristine montmorillonite. SEM-EDS and XPS analyses revealed that Cs+ and Sr2+ were ion-exchanged with Na+ on the surface functional groups formed following NaOH treatment. The performance of NaOH-treated montmorillonite was stable following gamma-ray irradiation (at 6Gyh1 for 30min) and across a broad range of pHs (3 to 11), exhibiting a high distribution coefficient (Kd) of 1.5103 mL g1 for Cs+ (1.58mg L1) and 3.7103 mL g1 for Sr2+ (1.64mg L1) under groundwater conditions where various cations including Na+, K+, and Ca2+ (V/m=1 L/g) were present. The proposed method demonstrated great improvement of the sorption capacity of an abundant and inexpensive montmorillonite.

published proceedings

  • Applied Surface Science

author list (cited authors)

  • Kim, Y., Kim, Y. K., Kim, J. H., Yim, M., Harbottle, D., & Lee, J. W.

complete list of authors

  • Kim, Yonghwan||Kim, Yun Kon||Kim, Jung Hwan||Yim, Man-Sung||Harbottle, David||Lee, Jae W