A Solvent Extraction-Liquid Scintillation Method for Assay of Uranium and Thorium in Phosphate-Containing Material
| Autor: | W.J. McDowell, John W. McKlveen, Edward J. Bouwer |
|---|---|
| Rok vydání: | 1979 |
| Předmět: |
inorganic chemicals
Nuclear and High Energy Physics Tertiary amine 020209 energy Radiochemistry Liquid scintillation counting Thorium chemistry.chemical_element 02 engineering and technology Actinide Uranium Condensed Matter Physics complex mixtures chemistry.chemical_compound 020303 mechanical engineering & transports 0203 mechanical engineering Nuclear Energy and Engineering chemistry Nitric acid Scintillation counter 0202 electrical engineering electronic engineering information engineering Trioctylphosphine oxide Nuclear chemistry |
| Zdroj: | Nuclear Technology. 42:102-111 |
| ISSN: | 1943-7471 0029-5450 |
| DOI: | 10.13182/nt79-a32166 |
| Popis: | A method utilizing solvent extraction coupled with liquid scintillation spectrometry has been developed for the assay of uranium and thorium in fertilizers and phosphate-containing minerals and chemicals. Trioctylphosphine oxide in toluene is used to extract uranium and thorium from a perchloric and nitric acid solution, with phosphate interference being suppressed by the addition of aluminum ion. The uranium and thorium are stripped from this solution, and uranium is separated from the thorium by selective reextraction of uranium into a scintillator with Adogen 364 (tertiary amine) sulfate. The thorium remaining in the aqueous is reextracted into another scintillator with (primary) 1-nonyldecylamine sulfate. Both nuclides are counted separately in a high-resolution liquid scintillation spectrometer. The sensitivity of the counting method is enhanced by the use of pulse-shape rejection of the beta--gamma background. Results indicate a detection threshold of 0.0038 pCi of uranium (1.1 part/10/sup 8/) with a 1000-min counting time. Reproducibility of +- 2.5% was found at the 50-ppM level. For thorium detection, thresholds are 4 part/10/sup 13/ for the same counting time with +- 3.0% average recovery of /sup 230/Th and 7 part/10/sup 8/ of /sup 232/Th. |
| Databáze: | OpenAIRE |
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