Preparation and Characterization of Zeolite‐Containing Composite Sheet for Decontamination of Radioactive Ions Dissolved in Water

The efficient and effective decontamination technologies of radioactive ions from soil and water have been required after the Fukushima No. 1 nuclear power plant accident. In this study, we prepared a zeolite‐containing composite sheet for decontamination of radioactive ions present in water, and evaluated its cesium adsorption behavior in some model experiments. The composite sheet increased in the amount of adsorbed cesium ion with increasing cesium ion concentration in water in batch experiment. In filtration experiment, the maximum adsorption ratio of cesium ion reached 98%, depending on the number of plied sheets. Although the composite sheet had high adsorption ratios of both cesium and strontium ions dissolved in pure water, almost no adsorption of Ce+ or Sr2+ was observed when seawater was used in place of pure water. Moreover, once cesium‐adsorbed sheet released some amounts of cesium ion, when 0.1M NaOH or seawater was used in soaking treatment.