A comparative study using liquid scintillation counting to determine $^{63}$Ni in low and intermediate level radioactive waste

comparative study using liquid scintillation counting was performed to measure $^{63}$Ni in low and intermediate level radioactive waste. Three dimethylglyoxime (DMG)-based radiochemical procedures (solvent extraction, precipitation, extraction chromatography) were investigated, the solvent extraction method being considered as the reference method. Theoretical speciation calculations enabled to better understand the chemical reactions involved in the three protocols and to optimize them. In comparison to the method based on DMG precipitation, the method based on extraction chromatography allowed to achieve the best results in one single step in term of recovery yield and accuracy for various samples.