Radioactive cesium (137Cs) is the most dangerous radioactive contaminant associated with nuclear fallout and radioactive liquid waste. In 2011, a large amount of radioactive cesium unfortunately leaked and spread over a large area of the water environment proximal to the nuclear accident sites at the Fukushima Daiichi nuclear power station. A variety of cesium adsorbents, including zeolites, calixarene, aluminum molybdophosphate, and metal ferrocyanide such as prussian blue(PB), were extensively investigated for their ability to remove 137Cs from water. However, these adsorbents cannot be used in an open environment because there is no easy approach to collection after use.
Although various magnetic nanoparticle (MNPs) coated with PB were recently reported to treat 137Cs-contaminated water because they can be magnetically separated from a water simply by application of an external magnet, the MNPs synthesized by a co-precipitation method tend to offer a poor magnetic separation properties and a low specific surface area for adsorption due to the poor size uniformity and crystallinity of MNPs. Furthermore, an interlayer such as poly(diallyldimethylammonium chloride) to coat the surface of MNP with PB using electrostatic interaction necessitate a multistep procedure and does not seem to be versatile enough because it is difficult to control the reproducibility and scale-up of the process.
In our paper of “Prussian blue-functionalized magnetic nanoclusters for the removal of radioactive Cesium from water”, PB-coated magnetic nanocluster (PB-MNC) with efficient removal performance of cesium and rapid magnetic separation property of the absorbent from water were prepared by simple reaction of magnetic nanocluster (MNC), synthesized via the hydrothermal method for uniform size, and good crystallinity of nanoparticles, with anionic [Fe(CN)6]4- under acidic conditions without an interlayer. These simple synthetic procedure developed in our paper allows the PB-MNC can be prepared on a large scale.
TEM images, XRD diffraction, and FTIR analysis indicated that MNC were successfully coated with PB. PB-MNC exhibited superparamagnetic behaviors with a saturation magnetization of 27.5 emu g–1. This value was higher than the corresponding values obtained from other magnetic cesium adsorbents. The adsorption of cesium onto the nanoparticle surfaces fit well to a Langmuir isotherm model with a maximum adsorption capacity of 45.87 mg/g, much higher than the adsorption capacities of other Prussian blue functionalized adsorbents. In addition, a high 137Cs removal efficiency was obtained, exceeding 99.28% of the radioactive cesium present in an aqueous solution containing 137Cs even in the presence of 3000 ppm competing ions such as K+ , Na+, Ca2+, and Mg2+. Therefore, PB-MNC demonstrated excellent potential for the treatment of 137Cs-contaminated water
Hee-Man Yang1 , Sung-Chan Jang2,3, Sang Bum Hong1, Kune-Woo Lee1, Changhyun Roh3,Yun Suk Huh2,
Bum-Kyoung Seo1.Show Affiliations
- Decontamination & Decommissioning Research Division, Korea Atomic Energy Research Institute, Daedeok-daero 989-111, Yuseong-gu, Daejeon 305-353, Republic of Korea
- Department of Biological Engineering, Biohybrid Systems Research Center, Inha University, Incheon 402-751, Republic of Korea
- Biotechnology Research Division, Advanced Radiation Technology Institute (ARTI), Korea Atomic Energy Research Institute (KAERI), Jeongeup, Jeonbuk 580-185, Republic of Korea
Prussian blue-functionalized magnetic nanoclusters were fabricated for the highly efficient removal of radioactive cesium (such as 137Cs) and rapid magnetic separation of absorbent from 137Cs-contaminated water. The magnetic nanoclusters, synthesized via the hydrothermal method, were coated with Prussian blue (PB) via a simple reaction with potassium hexacyanoferrate under acidic conditions. The resulting Prussian blue-functionalized magnetic nanoclusters had a large distribution coefficient, even in the presence of 3000 ppm competing ions such as K+, Na+, Ca2+ and Mg2+, and excellent removal efficiency (>99.7%) of radioactive cesium from contaminated water. Furthermore, they possess good saturation magnetization values (27.5 emu/g), allowing for rapid separation from an aqueous solution using an external magnetic field. Therefore, these magnetic adsorbents have promising applications for the treatment of radioactive cesium-contaminated water.Go To Journal of Alloys and Compounds