Standard Test Method for Determination of Uranium or Plutonium Isotopic Composition or Concentration by the Total Evaporation Method Using a Thermal Ionization Mass Spectrometer

SIGNIFICANCE AND USE
5.1 The total evaporation method is used to measure the isotopic composition of uranium and plutonium materials, and may be used to measure the elemental concentrations of the two elements when employing the IDMS technique.  
5.2 Uranium and plutonium compounds are used as nuclear reactor fuels. In order to be suitable for use as a nuclear fuel the starting material must meet certain criteria, such as found in Specifications C757, C833, C753, C776, C787, C967, C996, C1008, or as specified by the purchaser. The uranium concentration, plutonium concentration, or both, and isotope abundances are measured by thermal ionization mass spectrometry following this method.  
5.3 The total evaporation method allows for a wide range of sample loading with no significant change in precision or accuracy. The method is also suitable for trace-level loadings with some loss of precision and accuracy. The total evaporation method and modern instrumentation allow for the measurement of minor isotopes using ion counting detectors, while the major isotope(s) is(are) simultaneously measured using Faraday cup detectors.  
5.4 The new generation of miniaturized ion counters allow extremely small samples, in the picogram range, to be measured via the total evaporation method. The method may be employed for measuring environmental or safeguards inspection samples containing nanogram quantities of uranium or plutonium. Very small loadings require special sample handling and careful evaluation of measurement uncertainties.  
5.5 Typical uranium analyses are conducted using sample loadings between 50 nanograms and several micrograms. For uranium isotope ratios the total evaporation method had been used in several recent NBL isotopic certified reference material (CRM) characterizations (for example (2, 3)). A detailed comparison of the total evaporation data on NBL uranium CRMs analyzed by the MAT 261 and TRITONTM instruments is provided in Ref (5). For total evaporation, plutonium analyses ...
SCOPE
1.1 This method describes the determination of the isotopic composition, or the concentration, or both, of uranium and plutonium as nitrate solutions by the total evaporation method using a thermal ionization mass spectrometer (TIMS) instrument. Purified uranium or plutonium nitrate solutions are deposited onto a metal filament and placed in the mass spectrometer. Under computer control, ion currents are generated by heating of the filament(s). The ion currents are continually measured until the whole sample is exhausted. The measured ion currents are integrated over the course of the measurement and normalized to a reference isotope ion current to yield isotope ratios.  
1.2 In principle, the total evaporation method should yield isotope ratios that do not require mass bias correction. In practice, samples may require this bias correction. Compared to the conventional TIMS method described in Test Method C1625, the total evaporation method is approximately two times faster, improves precision of the isotope ratio measurements by a factor of two to four, and utilizes smaller sample sizes. Compared to the C1625 method, the total evaporation method provides “major” isotope ratios 235U/238U and 240Pu/239Pu with improved accuracy.  
1.3 The total evaporation method is prone to biases in the “minor” isotope ratios (233U/238U, 234U/238U, and 236U/238U ratios for uranium materials and 238Pu/239Pu, 241Pu/239Pu, 242Pu/239Pu, and 244Pu/239Pu ratios for plutonium materials) due to peak tailing from adjacent major isotopes. The magnitude of the absolute bias is dependent on measurement and instrumental characteristics. The relative bias, however, depends on the relative isotopic abundances of the sample. The use of an electron multiplier equipped with an energy filter may eliminate or diminish peak tailing effects. Measurement of the abundance sensitivity of the instrument may be used to ensure that such biases are negligible, or ...

General Information

Status
Historical
Publication Date
31-Dec-2016
Technical Committee
Drafting Committee
Current Stage
Ref Project

Relations

Buy Standard

Standard
ASTM C1672-17 - Standard Test Method for Determination of Uranium or Plutonium Isotopic Composition or Concentration by the Total Evaporation Method Using a Thermal Ionization Mass Spectrometer
English language
20 pages
sale 15% off
Preview
sale 15% off
Preview
Standard
REDLINE ASTM C1672-17 - Standard Test Method for Determination of Uranium or Plutonium Isotopic Composition or Concentration by the Total Evaporation Method Using a Thermal Ionization Mass Spectrometer
English language
20 pages
sale 15% off
Preview
sale 15% off
Preview

Standards Content (Sample)

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.
Designation: C1672 − 17
Standard Test Method for
Determination of Uranium or Plutonium Isotopic
Composition or Concentration by the Total Evaporation
1
Method Using a Thermal Ionization Mass Spectrometer
This standard is issued under the fixed designation C1672; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope that such biases are negligible, or may be used to bias correct
the minor isotope ratios.
1.1 This method describes the determination of the isotopic
composition, or the concentration, or both, of uranium and 1.4 The values stated in SI units are to be regarded as
plutonium as nitrate solutions by the total evaporation method standard. When non-SI units are provided in parentheses, they
using a thermal ionization mass spectrometer (TIMS) instru- are for information only.
ment. Purified uranium or plutonium nitrate solutions are
1.5 This standard may involve the use of hazardous mate-
deposited onto a metal filament and placed in the mass
rials and equipment. This standard does not purport to address
spectrometer. Under computer control, ion currents are gener-
all of the safety concerns, if any, associated with its use. It is
ated by heating of the filament(s). The ion currents are
the responsibility of the user of this standard to establish
continuallymeasured until the whole sample is exhausted.The
appropriate safety and health practices and determine the
measured ion currents are integrated over the course of the
applicability of regulatory limitations prior to use.
measurementandnormalizedtoareferenceisotopeioncurrent
to yield isotope ratios.
2. Referenced Documents
2
1.2 In principle, the total evaporation method should yield
2.1 ASTM Standards:
isotope ratios that do not require mass bias correction. In
C753Specification for Nuclear-Grade, Sinterable Uranium
practice, samples may require this bias correction. Compared
Dioxide Powder
to the conventional TIMS method described in Test Method
C757Specification for Nuclear-Grade Plutonium Dioxide
C1625, the total evaporation method is approximately two
Powder for Light Water Reactors
times faster, improves precision of the isotope ratio measure-
C776Specification for Sintered Uranium Dioxide Pellets
ments by a factor of two to four, and utilizes smaller sample
C787Specification for Uranium Hexafluoride for Enrich-
sizes. Compared to the C1625 method, the total evaporation
ment
235 238 240
method provides “major” isotope ratios U/ U and Pu/
C833Specification for Sintered (Uranium-Plutonium) Diox-
239
Pu with improved accuracy.
ide Pellets for Light Water Reactors
C859Terminology Relating to Nuclear Materials
1.3 The total evaporation method is prone to biases in the
233 238 234 238 236 238
C967Specification for Uranium Ore Concentrate
“minor” isotope ratios ( U/ U, U/ U, and U/ U
238 239 241 239
C996Specification for Uranium Hexafluoride Enriched to
ratios for uranium materials and Pu/ Pu, Pu/ Pu,
235
242 239 244 239
Less Than 5% U
Pu/ Pu, and Pu/ Pu ratios for plutonium materials)
C1008 Specification for Sintered (Uranium-Plutonium)
due to peak tailing from adjacent major isotopes. The magni-
3
DioxidePellets—Fast Reactor Fuel (Withdrawn 2014)
tude of the absolute bias is dependent on measurement and
C1068Guide for Qualification of Measurement Methods by
instrumental characteristics. The relative bias, however, de-
a Laboratory Within the Nuclear Industry
pends on the relative isotopic abundances of the sample. The
C1156Guide for Establishing Calibration for a Measure-
useofanelectronmultiplierequippedwithanenergyfiltermay
ment Method Used toAnalyze Nuclear Fuel Cycle Mate-
eliminate or diminish peak tailing effects. Measurement of the
rials
abundance sensitivity of the instrument may be used to ensure
1 2
ThistestmethodisunderthejurisdictionofASTMCommitteeC26onNuclear For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Fuel Cycle and is the direct responsibility of Subcommittee C26.05 on Methods of contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Test. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved Jan. 1, 2017. Published January 2017. Originally the ASTM website.
3
approved in 2007. Last previous edition approved in 2014 as C1672–07 (2014). The last approved version of this historical standard is referenced on
DOI: 10.1520/C1672-17. www.astm.org.
Copyright © ASTM International, 100 Barr Harbor
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: C1672 − 07 (Reapproved 2014) C1672 − 17
Standard Test Method for
Determination of Uranium or Plutonium Isotopic
Composition or Concentration by the Total Evaporation
1
Method Using a Thermal Ionization Mass Spectrometer
This standard is issued under the fixed designation C1672; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This method describes the determination of the isotopic composition and/or the concentration composition, or the
concentration, or both, of uranium and plutonium as nitrate solutions by the total evaporation method using a thermal ionization
mass spectrometric (TIMS) total evaporation method. spectrometer (TIMS) instrument. Purified uranium or plutonium nitrate
solutions are loadeddeposited onto a degassed metal filament and placed in the mass spectrometer. Under computer control, ion
currents are generated by heating of the filament(s). The ion beamscurrents are continually measured until the whole sample is
exhausted. The measured ion currents are integrated over the course of the run,measurement and normalized to a reference isotope
ion current to yield isotopicisotope ratios.
1.2 In principle, the total evaporation method should yield isotopicisotope ratios that do not require mass bias correction. In
practice, some samples may require this bias correction. When compared Compared to the conventional TIMS method, method
described in Test Method C1625, the total evaporation method is approximately two times faster, improves precision from two to
four fold, of the isotope ratio measurements by a factor of two to four, and utilizes smaller sample sizes. Compared to the C1625
235 238 240 239
method, the total evaporation method provides “major” isotope ratios U/ U and Pu/ Pu with improved accuracy.
233 238 234 238
1.3 The total evaporation method may leadis prone to biases in minor the “minor” isotope ratios ( U/ U, U/ U, and
236 238 238 239 241 239 242 239 244 239
U/ U ratios for uranium materials and Pu/ Pu, Pu/ Pu, Pu/ Pu, and Pu/ Pu ratios for plutonium materials)
due to peak tailing from adjacent major isotopes, depending on sample characteristics. The isotopes. The magnitude of the absolute
bias is dependent on measurement and instrumental characteristics. The relative bias, however, depends on the relative isotopic
abundances of the sample. The use of an electron multiplier equipped with an energy filter may eliminate or diminish peak tailing
effects. Measurement of instrumentthe abundance sensitivity of the instrument may be used to ensure that such biases are
negligible, or may be used to bias correct the minor isotope ratios.
1.4 The values stated in SI units are to be regarded as standard. When non-SI units are provided in parentheses, they are for
information only.
1.5 This standard may involve the use of hazardous materials and equipment. 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.
2. Referenced Documents
2
2.1 ASTM Standards:
C753 Specification for Nuclear-Grade, Sinterable Uranium Dioxide Powder
C757 Specification for Nuclear-Grade Plutonium Dioxide Powder for Light Water Reactors
C776 Specification for Sintered Uranium Dioxide Pellets
C787 Specification for Uranium Hexafluoride for Enrichment
C833 Specification for Sintered (Uranium-Plutonium) Dioxide Pellets for Light Water Reactors
C859 Terminology Relating to Nuclear Materials
C967 Specification for Uranium Ore Concentrate
1
This test method is under the jurisdiction of ASTM Committee C26 on Nuclear Fuel Cycle and is the direct responsibility of Subcommittee C26.05 on Methods of Test.
Current edition approved Jan. 1, 2014Jan. 1, 2017. Published February 2014January 2017. Originally approved in 2007. Last previous edition approved in 20072014 as
C1672C1672 – 07 (2014).–07. DOI: 10.1520/C1672-07R14.10.1520/C1672-17.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 1
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.