Determination Of Low ~(137)cs Concentration In Seawater Using Ammonium 12-molybdophosphate Adsorption And Chemical Separation Method

摘要

A new method has been developed for analyzing ~(137)Cs in a small volume of seawater. Ammonium 12-molybdophosphate (AMP) was used two times during pretreatment procedure. The first step was to adsorb ~(137)Cs in seawater samples into AMP in order to reduce sample volume, and the second was to remove ~(87)Rb, interference nuclide for β counting. The AMP adsorbing ~(137)Cs was dissolved by sodium hydroxide solution, and then ~(137)Cs was finally formed to be cesium chloroplatinate precipitate by adding 10% hexachloroplatinic acid. The beta rays emitted from ~(137)Cs were measured with a low background gas-proportional α/β counter. This method was applied to several seawater samples taken in the East Sea of Korea. Compared to the routinely used γ-spectrometry method, this new AMP method was reliable and suitable for analyzing ~(137)Cs in deep seawater.