ASTM_C_1254_-_18.pdf

Designation:C125418Standard Test Method forDetermination of Uranium in Mineral Acids by X-RayFluorescence1This standard is issued under the fixed designation C1254;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the steps necessary for thepreparation and analysis by X-ray fluorescence(XRF)ofmineral acid solutions containing uranium.1.2 This test method is valid for those solutions containing0.05 to 20 g uranium/L as presented to the spectrometer.Higher concentrations may be covered by appropriate dilu-tions.1.3 The values stated in SI units are to be regarded as thestandard.1.4 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.Specific precautionary statements are given in Section 9 andNote 1.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2C859 Terminology Relating to Nuclear MaterialsD1193 Specification for Reagent WaterE135 Terminology Relating to Analytical Chemistry forMetals,Ores,and Related Materials2.2 Other Document:ANSI/HPS N43.22001 Radiation Safety for X-ray Diffrac-tion and Fluorescence Analysis Equipment33.Terminology3.1 Definitions:3.1.1 See Terminologies E135 and C859 for definitions ofterms applicable to this test method.4.Summary of Test Method4.1 Solution standards containing 0.025 g uranium/L to 20 guranium/L and an appropriate internal standard(usually eitheryttrium or strontium),unless a scatter line is used in lieu of,areplaced in a liquid sample holder of an X-ray spectrometer andexposed to an X-ray beam capable of exciting the uraniumL-alpha emission line and the appropriate emission line for theinternal standard(usually the K-alpha line).The intensitiesgenerated are measured by an appropriate detector.The inten-sity ratio values obtained from this data are used to calibratethe X-ray analyzer.5.Significance and Use5.1 This test method is applicable to aqueous solutions ofuranium containing 0.05 to 20 g uranium per litre of solutionpresented to the spectrometer.5.2 Either wavelength-dispersive or energy-dispersiveX-ray fluorescence systems may be used provided the softwareaccompanying the system is able to accommodate the use ofinternal standards.6.Interferences6.1 This test method requires the use of an appropriateinternal standard.Care must be taken to ascertain that samplesanalyzed by this test method do not contain the internalstandard element or that this contamination has been correctedfor mathematically whenever present.Such corrections are notaddressed in this test method.6.2 Alternatively a scatter line may be used as internalstandard in which case the preparation of internal standard1This test method is under the jurisdiction ofASTM Committee C26 on NuclearFuel Cycle and is the direct responsibility of Subcommittee C26.05 on Methods ofTest.Current edition approved Oct.1,2018.Published November 2018.Originallyapproved in 1993.Last previous edition approved in 2013 as C1254 13.DOI:10.1520/C1254-18.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from the Health Physics Society,McLean,Virginia,22101.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 solutions and subsequent doping of samples and calibrationstandards is unnecessary.46.3 Sample must not contain significant concentration ofany elements that have mass absorption edges that fall betweenthe energies of the uranium L-alpha line and the internalstandard line.6.4 Care must also be taken that the choice of internalstandard and sample medium are compatible;that is,do not useyttrium with solutions containing HF or strontium with thosehaving H2SO4.7.Apparatus7.1 X-Ray SpectrometerThis test method is valid for eitherenergy-dispersive or wavelength