Sv. Zablotsky et al., IMPROVEMENTS IN THE METHOD OF SR-90 EXTRACTION FROM ENVIRONMENTAL-SAMPLES WITH DICYCLOHEXYL-18-CROWN-6, Kerntechnik, 60(5-6), 1995, pp. 262-264
Yields in each step of a chemical procedure to isolate strontium from
environmental samples for radiometric determination of Sr-90 were dete
rmined. The method is based on nitric acid leaching followed by chroma
tographic extraction of strontium and radiometric determination of Sr-
90. Dicyclohexyl-18-crown-6 in tetrachloroethane, which is held as a l
iquid in pores of styrene-divinyl benzene beads, serves as the extract
ant. A key step is desorption from the chromatographic column by use o
f hot water, which has been optimized to recover 90 % of the strontium
. In conjunction with advanced radiometry, measuring Sr-90 activities
of the order of 0.1 Bq per sample is expected to be feasible.