title: The separation of 99Tc from low and medium-level radioactive wastes and its determination by inductively coupled plasma mass spectrometry.
abstract: A chemical separation method has been developed for the determination of (99)Tc in various types of radioactive wastes. Such a method includes (i) fusion with NaOH, (ii) extraction in a column containing methyltrioctylammonium chloride, (iii) extraction by solvent with N-benzoyl-N-phenylhydroxylamine and, (iv) measurement by inductively-coupled plasma mass spectrometry (ICP-MS). From the performance standpoint, the recovery of (99)Tc, using (99m)Tc as a yield tracer, is higher than 70%. This analytical method, as developed, ensures effective decontamination with respect to the radionuclides, insofar the decontamination factors are greater than 10(+5), whenever the residual activity may be measured. Taking into account a 3sigma counting error, the detection limit obtained with the ICP-MS technique is 1.9 mBq/ml; the method enabling hence to detect activities as low as 0.3 Bq/g, with analysed samples of 0.2 g and a radiochemical yield of 70%. Studies have been dedicated to the (99)Tc measurement, using the electrothermal vaporization ICP-MS technique, which lowers the detection limit by a factor 10, with the standard solution (0.3 pg/ml), compared with the previous ICP-MS technique.
authors.affiliation: Commissariat à l'Energie Atomique, Centre de Valduc, Service Contôle Essais, Is sur Tille, France.
authors.forename: P
authors.initials: P
authors.lastname: Hepiegne
authors.forename: D
authors.initials: D
authors.lastname: Dall'ava
authors.forename: R
authors.initials: R
authors.lastname: Clement
authors.forename: J P
authors.initials: JP
authors.lastname: Degros