Combined extraction chromatography and scintillation detection for off-line and on-line monitoring of strontium in aqueous solutions

Application of a new sensor materials, which combine extraction chromatography and scintillation detection is presented. The resultant sensor embodies the simultaneous dual functionality of selective extraction and radiation detection, which has been applied towards off-line and on-line monitoring of radiostrontium in aqueous solutions. The sensor materials are (1) a mixture of commercially available Sr-selective extraction chromatographic resin and granular scintillator, (2) bis-4,4'(5')-tert-butylcyclohexano-18-crown-6 (DtBuCH18C6) in 1-octanol coated on the surface of a scintillating glass and (3) inert chromatographic resin impregnated with the organic fluors, 2,5 diphenyloxazole, (PPO) and 1-4 bis(4-methyl-5-phenyloxazol-2-yl) benzene, (DM-POPOP) and either DtBuCH18C6 in 1-octanol or a proprietary extractant. For off-line measurements, the sensor materials are used in the same manner as the commercially available extraction chromatographic resin, but rather than eluting the activity from the column, the scintillating extraction column is placed in a scintillation vial and counted without the introduction of liquid scintillation cocktail. For on-line measurements, the sensor materials are used in conjunction with a flow-cell scintillation detection system to assess the activity retained by the extractant in real-time. Characterization of the detection efficiency and regeneration capability of the extractive scintillator materials is evaluated. (author)