Significance and Use
Uranyl nitrate solution is used as a feed material for conversion to the hexafluoride as well as for direct conversion to the oxide. In order to be suitable for this purpose, the material must meet certain criteria for uranium content, isotopic composition, acidity, radioactivity, and impurity content. These methods are designed to show whether a given material meets the specifications for these items described in Specification C788.
An assay is performed to determine whether the material has the specified uranium content.
Determination of the isotopic content of the uranium is made to establish whether the effective fissile content is in accordance with the purchaser’s specifications.
Acidity, organic content, and alpha, beta, and gamma activity are measured to establish that they do not exceed their maximum limits.
Impurity content is determined to ensure that the maximum concentration limit of certain impurity elements is not exceeded. Impurity concentrations are also required for calculation of the equivalent boron content (EBC), and the total equivalent boron content (TEBC).
1.1 These test methods cover procedures for the chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade uranyl nitrate solution to determine compliance with specifications.
1.2 The analytical procedures appear in the following order:
|Determination of Uranium||7|
|Specific Gravity by Pycnometry||15-20|
|Free Acid by Oxalate Complexation||21-27|
|Determination of Thorium||28|
|Determination of Chromium||29|
|Determination of Molybdenum||30|
|Halogens Separation by Steam Distillation||31-35|
|Fluoride by Specific Ion Electrode||36-42|
|Halogen Distillate Analysis: Chloride, Bromide, and Iodide by|
|Determination of Chloride and Bromide||44|
|Determination of Sulfur by X-Ray Fluorescence||45|
|Sulfate Sulfur by (Photometric) Turbidimetry||46|
|Phosphorus by the Molybdenum Blue (Photometric) Method||54-61|
|Silicon by the Molybdenum Blue (Photometric) Method||62-69|
|Carbon by Persulfate Oxidation-Acid Titrimetry||70|
|Conversion to U3O8||71-74|
|Boron by Emission Spectrography||75-81|
|Impurity Elements by Spark Source Mass Spectrography||82|
|Isotopic Composition by Thermal Ionization Mass Spectrometry||83|
|Uranium-232 by Alpha Spectrometry||84-90|
|Total Alpha Activity by Direct Alpha Counting||91-97|
|Fission Product Activity by Beta Counting||98-104|
|Entrained Organic Matter by Infrared Spectrophotometry||105|
|Fission Product Activity by Gamma Counting||106|
|Determination of Arsenic||107|
|Determination of Impurities for the EBC Calculation||108|
|Determination of Technetium 99||109|
|Determination of Plutonium and Neptunium||110|
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 5.