Determination of α Nuclides in High Level Liquid Waste by Combining Extraction, Liquid Scintillation Counting, and α Spectrometry

The approach combining solvent extraction, liquid scintillation counting (LSC), and α spectrometry has taken advantages of high counting efficiency (nearly 100%) of LSC for α radiation and high energy resolution of α spectrometry. Since the extraction processes are much shorter than those reported and no complicated procedures are required for preparation of α plate source, the new approach is easy to be used to determine α nuclides in mixed solution. Good agreements are achieved for real samples of high level liquid waste (HLLW) between accepted data and those obtained by this new approach. To deal with the interference with α/β discrimination from large amount of ⁹⁰Y in HLLW, two ways were proposed to decrease the radioactivity of ⁹⁰Y in sample, i.e. delaying measurement or diluting the sample, which can be used under different circumstances.