Radiochemical separation of 63Ni from activation products and estimation by liquid scintillation counting

63Ni is one of the most abundant, long lived radionuclide associated with reactor wastes. Owing to its very low beta energy it can be conveniently called as Hard-to-Detect (HTD) radionuclide. Separation of 63Ni from various activation products was achieved using a 2 stage process; anion exchange resin followed by organic extraction. 63Ni activity was evaluated based on the cross section data and compared with experimental values. 63Ni activity was quantitatively determined using Liquid Scintillation Counting (LSC) and stable Ni was determined by TXRF. This methodology can be adopted for quantitative estimation of 63Ni from irradiated reactor components to qualify the clearance level for disposal of materials during decommissioning. (author)