Significance and Use
4.1 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.
4.1.1 An assay is performed to determine whether the material has the specified uranium content.
4.1.2 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.
4.1.3 Acidity, organic content, and alpha, beta, and gamma activity are measured to establish that they do not exceed their maximum limits.
4.1.4 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).
Scope
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:
Sections
Determination of Uranium
8
Specific Gravity by Pycnometry
16 – 21
Free Acid by Oxalate Complexation
22 – 28
Determination of Thorium
29
Determination of Chromium
30
Determination of Molybdenum
31
Halogens Separation by Steam Distillation
32 – 36
Fluoride by Specific Ion Electrode
37 – 43
Halogen Distillate Analysis: Chloride, Bromide, and Iodide by
Amperometric Microtitrimetry
44
Determination of Chloride and Bromide
45
Determination of Sulfur by X-Ray Fluorescence
46
Sulfate Sulfur by (Photometric) Turbidimetry
47
Phosphorus by the Molybdenum Blue (Photometric) Method
55 – 62
Silicon by the Molybdenum Blue (Photometric) Method
63 – 70
Carbon by Persulfate Oxidation-Acid Titrimetry
71
Conversion to U3O8
72 – 75
Boron by Emission Spectrography
A
Impurity Elements by Spark Source Mass Spectrography
77
Isotopic Composition by Thermal Ionization Mass Spectrometry
78
Uranium-232 by Alpha Spectrometry
79 – 85
Total Alpha Activity by Direct Alpha Counting
86 – 92
Fission Product Activity by Beta Counting
93 – 99
Entrained Organic Matter by Infrared Spectrophotometry
100
Fission Product Activity by Gamma Counting
101
Determination of Arsenic
102
Determination of Impurities for the EBC Calculation
103
Determination of Technetium 99
104
Determination of Plutonium and Neptunium
105
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.4 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 6.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
