DOE RESL: CHEM-TP-A.20: Actinide Separations for Alpha Spectrometry Using Neodymium Fluoride Coprecipitation
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Official Method Name
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Actinide Separations for Alpha Spectrometry using Neodymium Fluoride Coprecipitation |
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Current Revision
| May 1999 |
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Media
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WATER |
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Instrumentation
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Alpha Spectrometer/Counter |
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Method Subcategory
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Radiochemical |
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Method Source
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Citation
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Brief Method Summary
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Note: This procedure supersedes RESL ACB-TP-A.20 (Rev 1). Air filters, 10-g soil, 500-mL water, and 5-g vegetation-ash samples are fused in potassium fluoride followed by a pyrosulfate fusion. The flux is dissolved in dilute hydrochloric acid and thorium, uranium, plutonium, and americium are coprecipitated on barium sulfate. These actinides can be directly coprecipitated from water samples on Barium sulfate, if total decomposition is not necessary. The barium sulfate is dissolved and reprecipitated in the presence of diethylenetriamine-pentaacetic acid (DPTA) to separate the actinides from barium sulfate. The filtrate is wet ashed, fused in a pyrosulfate flux, and fusion cake dissolved in dilute nitric acid. Thorium is separated from the other actinides by coprecipitation on ceric iodate. Uranium, plutonium, and americium are separated sequentially, one from the other, by oxidizing them to their highest oxidation states followed by a series of coprecipitations of the nuclides. The isolated nuclides are coprecipitated on neodymium fluoride, filtered and determined by alpha spectrometry. |
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Scope and Application
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The procedure prepares air filters, soil, water, and vegetation samples for determination of thorium (Th), uranium (U), plutonium (Pu), and americium (Am). |
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Applicable Concentration Range
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Low-level samples: 5-20 dpm of alpha tracer and a comparable or lesser activity of analyte nuclide(s) |
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Interferences
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(A) Neptunium presence: Procedure will not work in the presence of neptunium because neptunium is incompletely separated from the other nuclides. (B) Cross contamination: To prevent cross contamination of samples and contamination of personnel, equipment, laboratory work area, and alpha spectrometry systems apply procedure to only low-level samples (see applicable conc. range). |
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Quality Control Requirements
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QC procedures based on internal laboratory requirements for radiochemical analysis. |
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Sample Handling
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To prevent cross contamination of samples and contamination of personnel, equipment, laboratory work area, and alpha spectrometry systems apply procedure to only low-level samples (see applicable conc. range). Analysts performing this procedure must be familiar with precautions associated with perchloric acid work (RESL Procedure -TP-IH.6). |
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Maximum Holding Time
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None given. |
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Relative Cost
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$51 to $200 |
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Sample Preparation Methods
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