DETERMINATION OF TC-99 IN REACTOR LOOP DECONTAMINATION LIQUID WASTE USING EXTRACTION CHROMATOGRAPHY

A new analytical method has been developed to determine Tc-99 in sampl es of aqueous radioactive waste containing high levers of Co-60 (10(3) -10(6) Bq/l) in mixed forms (simple cationic Co-60(2+) and coordinated complex forms). The method consists of selective extraction of the Tc -99 with a combination of cation exchange and solid-phase extraction r esins under strong acid conditions. Quantification of the isolated Tc- 99 is accomplished using liquid scintillation counting. The method pro vides high recoveries (>98%), is simpler than classical solvent extrac tion methods, eliminates the use of chlorinated organic solvents and t he time of analysis is reduced by a factor of 2 when compared to solve nt extraction methods.