Problems in reprocessing spent nuclear fuel

Technetium: behaviour during reprocessing of spent nuclear fuel and in environmental objects

“…115,116 The concentrations of stable ruthenium in samples are generally much higher than the concentrations of Tc, which hinders the determination of the latter element. Hence, the complete removal of 99 Ru as well as of 98 Mo and 100 Mo is essential for the successful determination of Tc. Initially, technetium is concentrated by chromatography using the TEVA TM Spec resin sorbent and then Tc is determined by ICP-MS.…”

“…Most Tc isotopes have short half-lives (from 0.81 s for 110 Tc to 61.2 days for 97m Tc). The exceptions are the above-mentioned 99 Tc isotope and two long-lived isotopes, viz., 97 Tc (t 1/2 = 2.6610 6 years) and 98 Tc (t 1/2 = 4.2610 6 years), which are prepared by irradiation of molybdenum with deuterons or protons.…”

“…Electrochemical methods are used along with traditional chemical methods for the preparation of solutions with the aim of stabilising technetium and actinides in the desired oxidation states when using the extraction technology of reprocessing of spent nuclear fuel. 98,99 It was demonstrated that the rate of electrolytic oxidation of Pu(0) to Pu(IV) and the yield of the product increased in the presence of technetium(VII) ions. Thus, the addition of Tc(VII) (70 mg litre 71 ) to a solution containing Pu(III) and hydrazine caused acceleration of oxidation of plutonium by a factor of *1.5 due, apparently, to catalytic decomposition of hydrazine with technetium ions.…”