A simple acid digestion using HCl–HNO3−NH4HF2 for rapid SF-ICP-MS determination of 237Np and Pu isotopes in steel and concrete samples

Rapid Method To Determine 137Cs, 237Np, and Pu Isotopes in Seawater by SF-ICP-MS

“…In the previously reported methods, ,, although HBr (8.6 M) was often used to elute Np and Pu in an AG MP-1 M resin chromatographic separation, the distribution of Pu and Np between HBr and anion exchange resins showed that Pu was not adsorbed and Np had a weak adsorption (approximately 10%), resulting in asynchronous elution of Np and Pu with the elution profile of Np lagging behind that of Pu as shown in Figure a. Thus, a larger amount of eluent was needed to ensure similar recoveries of Np and Pu.…”

“…In oxic seawater, most of the Np and Pu usually exist in the oxidation states of Np(V), Pu(IV), and Pu(V), 8 and an appropriate redox system is crucial because iron hydroxide coprecipitation provides better recovery of Np and Pu in the corresponding reduced states (Np(IV), Pu(III), and Pu(IV)). 20,29 Meanwhile, as a carrier, the increase of iron content was found to be beneficial for the recovery of Np and Pu at pH 8−9 20 ; however, our previous work found that excess iron causes the loss of Np during the anion exchange AG MP-1 M resin column separation, 39 which results in chemical fractionation between Np and Pu. Therefore, both the redox system and the amount of iron must be further optimized.…”