ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 38, Number 7
JKCSEZ 38(7)
February 20, 1994 

The measurement of trace amounts of uranium(Ⅵ) and thorium(Ⅵ) in the solutions containing high concentration of dissolved salts was carried out. The procedure using reversed phase liquid chromatography with trace enrichment techniques has been developed to cope with the high salt content of the samples. 2 ml of sample were passed through a small C18 reversed phase enrichment column with α-HIBA eluent (0.11 M, pH 5.5) where the uranium and thorium were separated from other constituents and concentrated. The uranium and thorium were then backflushed from the column onto a deactivated C18 reversed phase analytical column where furthe separation was achieved with a mixed eluent (pH3.0, 0.17M α-HIBA/0.0038 M 1-pentanesulfonate). The separated species were determined spectrophotometrically by postcolumn reaction with Arsenazo Ⅲ, the chromogenic reagent. Detection limits were found within 1 ppb range for both species.