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In this study, a hydrogel impregnated with powder activated carbon (PAC), MAA-PAC, was synthesized through the polymerization of acrylic acid (AA) and PB was immobilized using the carboxyl group of AA. In this process, an adsorbent with an enhancement of PB content and stability of immobilization was developed through the additional supply of Fe3+ ions by the layer by layer (LBL) assembly. XRD, FT-IR, SEM (EDS), TEM (EDS, mapping), and TG analyzes of the LBL and non-LBL groups were performed to confirm the change of PB content in the adsorbent as the LBL assembly was applied. The stability of PB immobilization was confirmed during the washing process after the synthesis of the adsorbent. When the LBL assembly process was applied as a PB immobilization strategy, the PB content in the adsorbent was improved and PB leakage was not observed during the washing process. The maximum adsorption (qm) for cesium in the MAA-PAC-PB LBL group that showed high PB content was 40.03 mg/g, and the adsorption isotherm was more suitable for the Langmuir model than the Freundlich model. The LBL group showed a high removal efficiency of 99.81% and a high DF value (525.88) for radioactive cesium (120 Bq/g). These results demonstrate the potential efficiency of the MAA-PAC-PB LBL group for the decontamination of radioactive cesium-contaminated water systems. Furthermore, it was verified that the LBL group of MAA-PAC-PB could be used as an adsorbent without an additional design of the existing water treatment facility. This can an economical decontamination method for removing radioactive cesium.

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In the event of nuclear accident in neighboring countries, radioactive materials may enter the country due to the effect of wind. In order to analyze the impact of nuclear accident in neighboring countries, we simulate model about Tianwan nuclear power plant accident in China. The 137 Cs was selected as the target radionuclides and The HYSPLIT 4 model of the NOAA and meteorological data which provided by NOAA/ARL were used to analyze the diffusion effect of 137 Cs and the effect of radionuclide fallout. 6 scenarios were developed to examine the effect of emission time of 137 Cs at a nuclear power plant accident and the effect of rainfall. As the simulation results showed that the higher the emission time, the higher was the concentration of 137 Cs present in the atmosphere and on the ground. Based on the calculation of the 137 Cs deposition rate (%) from Scenario I and Scenario II, it was found that the rainy season during the simulation period was deposited at a higher rate than during the dry season.