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

This paper presents the application of a new sensor materials, which combin e extraction chromatography and scintillation detection. The resultant sens or embodies the simultaneous dual functionality of selective extraction and radiation detection, which has been applied towards off-line and on-line m onitoring of radiostrontium in aqueous solutions. The sensor materials are (1) a mixture of commercially available Sr-selective extraction chromatogra phic resin and granular scintillator, (2) bis-4,4 ' (5 ')-tert-butylcyclohe xano-18-crown-6 (DtBuCH18C6) in I-octanol coated on the surface of a scinti llating glass and (3) inert chromatographic resin impregnated with the orga nic 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 proprieta ry extractant. For off-line measurements, the sensor materials are used in the same manner as the commercially available extraction chromatographic re sin, but rather than eluting the activity from the column, the scintillatin g extraction column is placed in a scintillation vial and counted without t he introduction of liquid scintillation cocktail. For on-line measurements, the sensor materials are used in conjunction with a flow-cell scintillatio n detection system to assess the activity retained by the extractant in rea l-time. Characterization of the detection efficiency and regeneration capab ility of the extractive scintillator materials is evaluated.