(548d) 3D-Interconnected PVA-Citric Acid Porous Hydrogels Embedded with Potassium Copper Hexacyanoferrate Nanoparticles for Enhanced Removal of Radionuclide Cesium
The as-obtained HPC demonstrates the superior Cs+ adsorption capacity and selectivity with significantly fast removal kinetics. In the adsorption isotherm, the HPC showed a very high Cs+ uptake of 667 mg/g KCuHCF at the saturated concentration. Moreover, the uptake process was exceptionally fast with 99.5 % of Cs+ ions adsorbed within 30 min, and the overall Cs+ removal was 99.9 % from a dilute Cs+ solution (9.18 ppm). Even when tested in seawater, the HPC exhibited almost unaltered Cs+ removal efficiency above 99.5 %, and the high distribution coefficient Kd value of 7.7 x 105 mL/g at an extremely low Cs+ concentration (0.67 ppm, V/m = 1000 ml/g), which highlighted the exceptional Cs+ affinity over all competing cations. In addition, this novel adsorbent represented the stable and high Cs+ removal efficiency of 99.9 % over a broad pH range from 2 to 10.
These enhanced removal properties are closely related to the synergistic effects of rich K+ contents in KCuHCF, well dispersion of the nanoparticles, and the fast swelling kinetics of the hydrogel matrix. Therefore, combined with the simple synthetic procedure and low production cost, the HPC is one of the most promising adsorbents for the rapid and selective removal of Cs+ from contaminated environments.