【国外标准】 Standard Practice for Removal of Uranium or Plutonium, or both, for Impurity Assay in Uranium or Plutonium Materials

5.1 This practice can be used to separate uranium or plutonium, or both, prior to the impurity analysis by various techniques. The removal of uranium and plutonium prior to quantification can improve the detection limits by minimizing the signal suppression caused by uranium or plutonium when using ICP techniques. Detection limits of ~1–10 part-per-billion (PPB) may be obtainable by matrix removal. Also, removal of the uranium and plutonium may allow the impurities analysis to be performed on a non-glove box enclosed instrument.5.2 Other test methods exist to determine impurities in uranium or plutonium. Test Method C1517 is able to determine many impurities in uranium at detection levels of ~1–10 part-per-million (ppm) by DC-Arc Spectrometry. Test Method C1287 is able to determine impurities in uranium at detection levels of ~100 ppb by ICP-MS. Test Method C1432 provides an alternative technique to remove plutonium by ion exchange prior to analysis of the impurities by ICP-AES.5.3 This practice can be used to demonstrate compliance with nuclear fuel specifications, for example, Specifications C753, C757, C776, C787, C788, and C996.1.1 This practice covers instructions for using an extraction chromatography column method for the removal of plutonium or uranium, or both, from liquid or digested oxides or metals prior to impurity measurements. Quantification of impurities can be made by techniques such as inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled plasma atomic emission spectrometry (ICP-AES), or atomic absorption spectrometry (AAS.)1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 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.