RESUMO
A hybrid extractive scintillating resin (HESR) was developed for the concentration and detection of radiocesium. The HESR comprised a cesium-selective potassium ferrierite ion-exchange powder embedded in porous polymeric scintillating beads. It was prepared by carrying out suspension polymerization of 4-methylstyrene with divinylbenzene, 2-(1-naphthyl)-4-vinyl-5-phenyloxazole fluor and ferrierite-K powder. A translucent column packed with the HESR was placed in a commercial flow-cell radiation detector for real-time detection of radiocesium. Measurements using the HESR detection system were compared with an on-line gamma-ray measurement using a NaI:Tl well detector containing a column of ferrierite-K powder/SiO2 or potassium-nickel ferrocyanate-polyacrylonitrile (KNiFC-PAN). The NaI:Tl well detector configuration quantified the gamma-ray from 137mBa, while the flow-cell detector primarily quantified the beta particles and conversion electrons of 137Cs. The minimum detectable concentration of the two detection modalities were calculated and shown to be lower than the maximum contaminant level in drinking water of 7.4 Bq/L (200 pCi/L).
