Enhanced removal performance and evaluative interaction mechanism of europium from an aqueous medium by microbial yeast-decorated zeolitic imidazolate framework hybrids

Abstract

In this work, novel microbial yeast-decorated zeolitic imidazolate framework-8 (ZIF-8/yeast) composites were successfully synthesized by an in situ growth method and applied in the efficient elimination of Eu(III) from a water medium. The adsorption performances and interaction mechanisms of Eu(III) by ZIF-8/yeast were determined by macroscopic experimental tests under diverse water chemistry conditions. The experimental results indicated that the adsorption performance of Eu(III) on ZIF-8/yeast hybrids could reach equilibrium within 15 min, which conformed to the pseudo-second-order kinetic pattern. The maximum adsorption capacity was 1.09 × 10⁻³ mol g⁻¹, which was higher than that of a series of adsorbents reported in previousliterature. The interaction mechanism between ZIF-8/yeast composites and Eu(III) was primarily revealed by electrostatic attraction, cation exchange and surface complexation. According to the research, the ZIF-8/yeast is considered a preferable adsorbent for the highly efficient purification and elimination of trivalent lanthanides from radioactive wastewater.