(533l) Magnetic Hierarchical Titanium-Ferrocyanide for the Removal of Radioactive Cs from Water
AIChE Annual Meeting
2022
2022 Annual Meeting
Environmental Division
Poster Session: Environmental Division
Wednesday, November 16, 2022 - 3:30pm to 5:00pm
The selective removal of 137Cs from contaminated seawater or radioactive liquid waste remains a challenge due to the presence of high concentrations of competing ions, such as K+, Na+, Mg2+, and Ca2+. In this study, the Magnetic hierarchical titanium-ferrocyanide were fabricated for the removal of radioactive cesium from water with enhanced Cs adsorption and magnetic separation properties. The new magnetic Cs adsorbent has a core–shell structure that comprises a Fe3O4 core, an interlayer ofSiO2, and a titanium-ferrocyanide-shell with hierarchical nanostructure. At first, the magnetic Fe3O4 nanoparticles synthesized via a hydrothermal reaction were coated with SiO2. Then, TiO2 were coated on the surface of SiO2 coated magnetic nanoparticles. Finally, the hierarchical titanium-ferrocyanide composed of 2-dimensional TiFC flakes was fabricated on the surface of core-shell Fe3O4@SiO2@TiO2 microparticles using a TiO2 sacrificial template via a simple reaction with potassium ferrocyanide (FC) based on the Kirkendall-type diffusion.
The resulting magnetic Cs adsorbent shows much faster Cs adsorption kinetics and higher adsorption capacity than other magnetic Cs adsorbents because of the increased effective surface area of hierarchical titanium-ferrocyanide. Detailed Cs adsorption studies revealed that the adsorption isotherms and kinetics could be effectively described by the Langmuir isotherm model and the pseudo-second-order model, respectively. Moreover, the Magnetic hierarchical titanium-ferrocyanide selectively adsorbed Cs even in the presence of various competing ions, such as K+, Na+, Mg2+, and Ca2+
In radioactive tests, even the low concentration of hf-TiFC (0.1 g/L) exhibited excellent removal performances in simulated groundwater and seawater with a high removal efficiency exceeding 99.85% at an initial 137Cs specific activity of approximately 70 Bq/g, which correspond to approximately 21.88 ppt. Therefore, our Magnetic hierarchical titanium-ferrocyanide has excellent potential for the treatment of various 137Cs-contaminated sources.
The resulting magnetic Cs adsorbent shows much faster Cs adsorption kinetics and higher adsorption capacity than other magnetic Cs adsorbents because of the increased effective surface area of hierarchical titanium-ferrocyanide. Detailed Cs adsorption studies revealed that the adsorption isotherms and kinetics could be effectively described by the Langmuir isotherm model and the pseudo-second-order model, respectively. Moreover, the Magnetic hierarchical titanium-ferrocyanide selectively adsorbed Cs even in the presence of various competing ions, such as K+, Na+, Mg2+, and Ca2+
In radioactive tests, even the low concentration of hf-TiFC (0.1 g/L) exhibited excellent removal performances in simulated groundwater and seawater with a high removal efficiency exceeding 99.85% at an initial 137Cs specific activity of approximately 70 Bq/g, which correspond to approximately 21.88 ppt. Therefore, our Magnetic hierarchical titanium-ferrocyanide has excellent potential for the treatment of various 137Cs-contaminated sources.