Fe₃O₄@ZIF-8: a magnetic nanocomposite for highly efficient UO₂²⁺ adsorption and selective UO₂²⁺/Ln³⁺ separation

Abstract

The magnetic nanocomposite FeO@ZIF-8 was for the first time used as an excellent adsorbent for the fast adsorption and separation of UO ions from aqueous solutions. This material exhibited an unprecedented adsorption capacity of 523.5 mg U per g and a remarkable selectivity towards UO/Ln at pH = 3.

In situ Preparation of Chitosan/ZIF-8 Composite Beads for Highly Efficient Removal of U(VI)

“…As shown in Figure 4, the maximum adsorption capacity of U(VI) is obtained as 629 mg•g −1 at pH = 3.0, and then gradually decreases as the pH increases. This is a similar trend to the work reported previously where Fe 3 O 4 @ZIF-8 (Min et al, 2017) and ZIF-8/PAN (Wang C. H. et al, 2018) were investigated for the adsorption of uranium. As shown in Figure 5, at pH of 3, U(VI) mainly exits in the form of UO22+ cation, as the pH increases, it will be hydrolyzed to oligomeric or colloidal species, such as (UO 2 ) 3 (OH)5+, (UO 2 ) 4 (OH)7+, (UO 2 ) 2 (OH)22+, and UO 2 (OH) + etc.…”

“…pH is an important parameter in uranium batch adsorption experiments (Zhang et al, 2017), due to its dramatic influence on the charge and active site of the sorbent and the speciation of U(VI) in solution (Min et al, 2017). Chitosan dissolves under acidic condition of pH = 2.…”

Magnetic Nanoparticles@Metal-Organic Framework Composites as Sustainable Environment Adsorbents

“…The results suggested the adsorption mechanism for U(VI) and Th(IV) over Fe 3 O 4 @AMCA-MIL53(Al) through the electrostatic interactions between the organic part of the magnetic nanocomposite and the radioactive metal ions and coordinate interactions between the metal ions and nitrogen in the framework. Min et al reported a novel Fe 3 O 4 @ZIF-8 magnetic nanocomposite for selective removal of UO 2 2+ from water, which showed a high adsorption capacity of 523.5 mg U g -1 [50]. Furthermore, Journal of Nanomaterials the selective separation of the UO 2 2+ from lanthanide results indicated that the obtained Fe 3 O 4 @ZIF-8 displayed remarkable selectivity performance for UO 2 2+ in the presence of lanthanides at pH 3.…”

Advanced Nanomaterials for Nuclear Energy and Nanotechnology

“…The magnetic nanocomposite Fe 3 O 4 @ZIF‐8 was first used as an excellent adsorbent for the fast adsorption and separation of UO 2 2+ ions from aqueous solution by Min et al The report showed that the adsorption capacity of Fe 3 O 4 @ZIF‐8 is 523.5 mg g −1 at pH = 3, which is the highest among MOFs. In addition, the composite possesses extraordinary separation performance for actinides from lanthanides.…”