A. Choukri et al., RADIOCHEMICAL SEPARATION OF U-ISOTOPE AND TH-ISOTOPE IN PHOSPHATE RICH SAMPLES FOR AGE-DETERMINATION, Radiochimica Acta, 65(2), 1994, pp. 137-139
A related radiochemical method for age determination of marine carbona
te samples (corals, shells, ...) has been modified for processing phos
phate samples. It is based on a single anion exchange column: U is ret
ained in 8 M HCl and Th in 8 M HNO3. Th is quantitatively fixed in the
latter medium provided [PO4(3-)] is < 0.1 M. Trials on real samples y
ield U and Th recoveries of 75 and 85%, respectively. This method cont
rasts with time-consuming procedures described in earlier works [1-5].