ASTM C1267-06

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: C1267 – 06
Standard Test Method for
Uranium by Iron (II) Reduction in Phosphoric Acid Followed
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by Chromium (VI) Titration in the Presence of Vanadium
This standard is issued under the fixed designation C1267; 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 Chromium(VI) Titration
,
C1346 Practice for Dissolution of UF from P-10 Tubes
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1.1 This test method, commonly referred to as the Modified
C1347 Practice for Preparation and Dissolution of Uranium
Davies and Gray technique, covers the titration of uranium in
Materials for Analysis
product, fuel, and scrap materials after the material is dis-
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2.2 NIST Standard:
solved. The test method is versatile and has been ruggedness
SRM 136e Potassium Dichromate (Oxidimetric Standard)
tested. With appropriate sample preparation, this test method
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2.3 NBL Standard:
can give precise and unbiased uranium assays over a wide
2 CRM 112A Uranium Metal Standard
variety of material types (1, 2). Details of the titration
procedure in the presence of plutonium with appropriate
3. Summary of Test Method
modifications are given in Test Method C1204.
3.1 Samples are prepared by dissolution techniques detailed
1.2 Uranium levels titrated are usually 20 to 50 mg, but up
in Practices C1346, C1347, or Refs (2), (3), and (4). Appro-
to 200 mg uranium can be titrated using the reagent volumes
priate uncertainties for sampling and weight determination
stated in this test method.
should be applied to the overall precision and bias calculations
1.3 This standard does not purport to address all of the
for the final result. Aliquants containing 20 to 200 mg of
safety concerns, if any, associated with its use. It is the
uranium are prepared by weight. The sample is fumed to
responsibility of the user of this standard to establish appro-
dryness after the appropriate acid treatment. The sample is
priate safety and health practices and determine the applica-
dissolved in dilute nitric acid or water prior to titration.
bility of regulatory limitations prior to use. For specific
3.2 Uraniumisreducedtouranium(IV)byexcessiron(II)in
safeguard and safety precaution statements, see Section 4.
concentrated phosphoric acid (H PO ) containing sulfamic
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2. Referenced Documents acid. The excess iron(II) is selectively oxidized by nitric acid
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(HNO ) in the presence of a molybdenum(VI) catalyst. After
2.1 ASTM Standards: 3
the addition of a vanadium(IV) solution, the uranium(IV) is
C696 Test Methods for Chemical, Mass Spectrometric, and
titrated with chromium(VI) to a potentiometric end point.
Spectrochemical Analysis of Nuclear-Grade Uranium Di-
3.3 Thechromium(VI)titrantmaybedeliveredmanuallyon
oxide Powders and Pellets
a weight or on a volumetric basis as specified by the facility
C799 Test Methods for Chemical, Mass Spectrometric,
titration procedure.
Spectrochemical, Nuclear, and RadiochemicalAnalysis of
3.3.1 If the titrant is delivered on a volumetric basis,
Nuclear-Grade Uranyl Nitrate Solutions
correctionstothevolumeoftitrantmaybeneededtoadjustfor
C1128 Guide for Preparation of Working Reference Mate-
the difference between the temperature of preparation and the
rials for Use in Analysis of Nuclear Fuel Cycle Materials
ambient temperature.
C1204 Test Method for Uranium in Presence of Plutonium
3.3.2 Automated titrators are facility specific and are not
by Iron(II) Reduction in Phosphoric Acid Followed by
explicitly addressed in this test method. However, automated
titrators which have comparable bias and precision may be
1
ThistestmethodisunderthejurisdictionofASTMCommitteeC26onNuclear used.
Fuel Cycle and is the direct responsibility of Subcommittee C26.05 on Methods of
3.3.3 There is an alternate, high precision (;0.005% RSD)
Test.
modified Davies and Gray titration, which is similar to the
CurrenteditionapprovedJuly1,2006.PublishedJuly2006.Originallyapproved
method covered in this procedure. In the high precision
in 1994. Last previous edition approved in 2000 as C1267–00. DOI: 10.1520/
C1267-06.
2
Theboldfacenumbersinparenthesesrefertothelistofreferencesattheendof
this standard.
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For referenced ASTM standards, visit the ASTM website, www.astm.org, or Available from National Institute of Standards and Technology (NIST), 100
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Bureau Dr., Stop 1070, Gaithersburg, MD 20899-1070, http://www.nist.gov.
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Standards volume information, refer to the standard’s Document Summary page on NewBrunswickLaboratory(NBL)CertifiedReferenceMaterialsCatalog(U.S.
the ASTM website. Department of Energy), http://www
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