ASTM C1441-04

This test method (Part A) utilizes FTIR spectroscopy to determine the percent Refrigerant-114 impurity in uranium hexafluoride. Refrigerant-114 is an example of an impurity gas in uranium hexafluoride. The detection of hydrocarbons, chlorocarbons, and partially or completely substituted halohydrocarbons in UF₆ (Part B) is governed by the provisions in Specification C 996.

1.1 This test method covers determining the concentrations of refrigerant-114, other carbon-containing and fluorine-containing compounds, hydrocarbons, and partially or completely substituted halohydrocarbons that may be impurities in uranium hexafluoride. The two options are outlined for this test method. They are designated as Part A and Part B.

1.1.1 To provide instructions for performing Fourier-Transform Infrared (FTIR) spectroscopic analysis for the possible presence of Refrigerant-114 impurity in a gaseous sample of uranium hexafluoride, collected in a "2S" container or equivalent at room temperature. The all gas procedure applies to the analysis of possible Refrigerant-114 impurity in uranium hexafluoride, and to the gas manifold system used for FTIR applications. The pressure and temperatures must be controlled to maintain a gaseous sample. The concentration units are in mole percent. This is Part A.

1.2 Part B involves a high pressure liquid sample of uranium hexafluoride. This method can be applied to the limits of detection for hydrocarbons, chlorocarbons, and partially or completely substituted halohydrocarbons as specified in Method C 996. The limits of detection are in units of mole percent concentration.

1.3 Part A pertains to Sections 7-10 and Part B pertains to sections 12-16.

1.4 These test options are applicable to the determination of hydrocarbons, chlorocarbons, and partially or completely substituted halohydrocarbons contained as impurities in uranium hexafluoride (UF₆). Gases such as carbon tetrafluoride (CF₄), which absorb infrared radiation in a region where uranium hexafluoride also absorbs infrared radiation, cannot be analyzed via these methods due to spectral overlap/interference.

1.5 These test options are quantitative and applicable in the concentration ranges from 0.0001 to 0.100 mole percent, depending on the analyte.

1.6 These test methods can also be used for the determination of non-metallic fluorides such as silicon tetrafluoride (SiF₄), phosphorus pentafluoride (PF₅), boron trifluoride (BF₃), and hydrofluoric acid (HF), plus metal-containing fluorides such as molybdenum hexafluoride (MoF₆). The availabilty of high quality standards for these gases is necessary for quantitative analysis.

1.7 These methods can be extended to other carbon-containing and inorganic gases as long as:

1.7.1 There are not any spectral interferences from uranium hexafluoride's infrared absorbances.

1.7.2 There shall be a known calibration or known "K" (value[s]) for these other gases.

1.8 The values stated in SI units are to be regarded as the standard.

1.9 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.