Rapid separation of nickel for 59Ni and 63Ni activity measurement in radioactive waste samples

A separation procedure of Ni has been described for the quantification of ⁵⁹Ni and ⁶³Ni in radioactive wastes discharged from nuclear power plants and various research activities related to the nuclear fuel cycle. For a rapid separation of the Ni-nuclides in sixteen sample solutions in 0.2 M NH₄-oxalate, a separation system composed of a peristaltic pump with sixteen channels and the same number of Ni–Resin columns was constructed. After sorption of the Ni-nuclides by sequentially passing 100 mL of the sample solution in 0.2 M NH₄-oxalate, 130 mL of 0.1 M NH₄-oxalate solution and 10 mL of deionized water as a wash into the columns, these were purely recovered by passing 10 mL of 9 M HCl into the Ni–Resin columns stacked in series on the anion exchange resin columns. The separation of the Ni-nuclides in sixteen sample solutions can be achieved within 7 h. The chemical yield of the proposed procedure is 92.3 ± 0.8 % (n = 5) and the gravimetric recovery in the preparation stage of the Ni-nuclide sources is also acceptable, 88.5 ± 1.3 % (n = 5).