The Removal of Strontium Ions from an Aqueous Solution Using Na-A Zeolites Synthesized from Kaolin

Woo-Ri Lim; Chang-Han Lee; Chung-Mo Lee

doi:10.3390/ma17030575

The Removal of Strontium Ions from an Aqueous Solution Using Na-A Zeolites Synthesized from Kaolin

Materials (Basel). 2024 Jan 25;17(3):575. doi: 10.3390/ma17030575.

Authors

Woo-Ri Lim¹, Chang-Han Lee², Chung-Mo Lee³

Affiliations

¹ KNU LAMP Research Center, KNU Institute of Basic Sciences, College of Natural Sciences, Kyungpook National University, Daegu 41566, Republic of Korea.
² Department of Environmental Administration, Catholic University of Pusan, Busan 46252, Republic of Korea.
³ Department of Geological Sciences and Institute for Future Earth, Pusan National University, Busan 46241, Republic of Korea.

Abstract

Sr²⁺ ions in an aqueous solution were removed using Na-A zeolites synthesized from kaolin, a natural mineral. Na-A zeolites with high crystallinity were synthesized using NaOH/kaolin mass ratios of 0.6 (ZK06) and 0.9 (ZK09). The adsorption reached equilibrium within 120 min. The adsorption data obtained from experiments for Sr²⁺ using ZK06 and ZK09 were appropriately analyzed with pseudo-second-order kinetic and Langmuir isotherm models. Comparing the maximum adsorption capacities (q_m) of ZK06 and ZK09 for Sr²⁺, the highest values were obtained at 1.90 and 2.42 mmol/g, respectively. Consequently, the Na-A zeolites synthesized from kaolin can be evaluated as adsorbents with high adsorption capacities for the removal of Sr²⁺, proportional to the degree of their crystallinity.

Keywords: Na-A zeolite; adsorption; crystallinity; radioactive waste; strontium.

Abstract

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