期刊名称：International Journal of Environmental Science and Development
印刷版ISSN：2010-0264
出版年度：2013
卷号：4
期号：6
页码：628-632
DOI：10.7763/IJESD.2013.V4.427
摘要：Two years having passed since the nuclear crisis at Fukushima, radioactive 137Cs with the half-life of ~ 30 years has come to the forefront of our largest concern.To gain an insight into current unsuccessful 137Cs decontamination from soil, heavily adhesive Cs adsorption, referred as specific Cs adsorption here, is highlighted for the layered clay minerals.Beside the interlayer Cs cations, a population of Cs is able to adsorb on the surfaces of open nanospaces with their sizes of ~ 0.3 nm and ~ 0.9 nm, which are formed by one- and two-clay nanosheet insertion into interlayer spaces.They are adsorbed on the surfaces of both the open nanospaces so strongly that cannot be removed even by the hydrochloric acid solution of pH 1.0, these open nanospaces thus acting as the specific Cs adsorption site.The characteristic local molecular structures as a clay-nanosheet edge and a wedge-shaped frayed part available in the open nanospaces are responsible for the specific Cs adsorption.Radioactive 137Cs that is not cleaned up after the decontamination work would originate from the specific Cs adsorption clarified here.The present findings unambiguously provide the molecular evidence of specific Cs adsorption and are thus of importance for further sophisticated decontamination of the radioactive Cs from the soil environment.
