ASTM C1413-2018 Standard Test Method for Isotopic Analysis of Hydrolyzed Uranium Hexafluoride and Uranyl Nitrate Solutions by Thermal Ionization Mass Spectromet.pdf

1、Designation: C1413 05 (Reapproved 2011)C1413 18Standard Test Method forIsotopic Analysis of Hydrolyzed Uranium Hexafluoride andUranyl Nitrate Solutions by Thermal Ionization MassSpectrometry1This standard is issued under the fixed designation C1413; the number immediately following the designation i

2、ndicates 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 method applies to the determinatio

3、n of isotopic composition in hydrolyzed nuclear grade uranium hexafluoride. Itcovers isotopic abundance of 235U between 0.1 and 5.0 % mass fraction, abundance of 234U between 0.0055 and 0.05 % massfraction, and abundance of 236U between 0.0003 and 0.5 % mass fraction. This test method may be applica

4、ble to other isotopicabundance providing that corresponding standards are available.1.2 This test method can apply to uranyl nitrate solutions. This can be achieved either by transforming the uranyl nitrate solutionto a uranyl fluoride solution prior to the deposition on the filaments or directly by

5、 depositing the uranyl nitrate solution on thefilaments. In the latter case, a calibration with uranyl nitrate standards must be performed.1.3 This test method can also apply to other nuclear grade matrices (for example, uranium oxides) by providing a chemicaltransformation to uranyl fluoride or ura

6、nyl nitrate solution.1.4 UnitsThe values stated in SI units are to be regarded as standard. No other units of measurement are included in thisstandard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of thi

7、s standard to establish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in t

8、he Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2C696 Test Methods for Chemical, Mass Spectrometric, and Spectrochemical An

9、alysis of Nuclear-Grade Uranium DioxidePowders and PelletsC753 Specification for Nuclear-Grade, Sinterable Uranium Dioxide PowderC761 Test Methods for Chemical, Mass Spectrometric, Spectrochemical, Nuclear, and Radiochemical Analysis of UraniumHexafluorideC776 Specification for Sintered Uranium Diox

10、ide Pellets for Light Water ReactorsC787 Specification for Uranium Hexafluoride for EnrichmentC788 Specification for Nuclear-Grade Uranyl Nitrate Solution or CrystalsC859 Terminology Relating to Nuclear MaterialsC996 Specification for Uranium Hexafluoride Enriched to Less Than 5 % 235UC1334 Specific

11、ation for Uranium Oxides with a 235U Content of Less Than 5 % for Dissolution Prior to Conversion toNuclear-Grade Uranium DioxideC1346 Practice for Dissolution of UF6 from P-10 TubesC1347 Practice for Preparation and Dissolution of Uranium Materials for Analysis1 This test method is under the jurisd

12、iction of ASTM Committee C26 on Nuclear Fuel Cycle and is the direct responsibility of Subcommittee C26.05 on Methods of Test.Current edition approved June 1, 2011Nov. 1, 2018. Published June 2011December 2018. Originally approved in 1999. Last previous edition approved in 20052011 asC1413 05.C1413

13、05 (2011). DOI: 10.1520/C1413-05R11.10.1520/C1413-18.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This doc

14、ument 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. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as

15、 appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1C1348 Specification for Blended Uranium Oxides with 235U

16、 Content of Less Than 5 % for Direct Hydrogen Reduction toNuclear Grade Uranium Dioxide (Withdrawn 2013)33. Terminology3.1 For definitions of terms used in this test method but not defined herein, refer to Terminology C859.4. Summary of Test Method4.1 After dilution of uranyl fluoride or uranyl nitr

17、ate solution, approximativelyapproximately 2 g of uranium are deposited ona rhenium filament. Analysis is performed in a thermal ionization mass spectrometer (TIMS), uranium is vaporized and ionizedthrough electrons emitted by a second filament; ions are extracted by an electric field, separated by

18、a magnetic field, and collectedby four collectors on mass 234, 235, 236, 238. The collectors are either faraday cups or electron multipliers collectors (ioncounting).4.2 Evaporation sequence and ion counting time are adjusted with the analysis of standard solutions of certified isotopic content.Nitr

19、ate and fluoride solutions lead to two different calibrations.5. Significance and Use5.1 Uranium hexafluoride used to produce nuclear fuel must meet certain criteria for its isotopic composition as described inSpecifications C787 and C996.6. Interferences6.1 This test method only applies to nuclear

20、grade uranium matrices (as defined in Specification C753, C776, C787, C788,C1334, or C1348). Large amount of impurities, which are found, for example, in uranium ore concentrates, may bias results. Apurification step may be necessary, as described in Specification C696.6.2 The type of acid used (HF

21、or HNO3) and its concentration will strongly influence the obtained isotopic results (see 9.211.2).7. Hazards7.1 Uranium hexafluoride is considered to be a hazardous material. It is a highly reactive and toxic substance in addition to itsradioactive properties.7.2 Hydrofluoric acid is a highly corro

22、sive acid that can severely burn skin, eyes, and mucous membranes. Hydrofluoric aciddiffers from other acids because the fluoride ion readily penetrates the skin, causing destruction of deep tissue layers. Unlike otheracids that are rapidly neutralized, hydrofluoric acid reactions with tissue may co

23、ntinue for days if left untreated. Familiarizationand compliance with the Safety Data Sheet is essential.8. Apparatus8.1 Thermal Ionization Mass Spectrometer (TIMS)Configured with four detectors.48.1.1 This test method requires a mass spectrometer with a resolution greater than 400 (full width at 1

24、% of peak height) andan abundance sensitivity of less than 105 (contribution of mass 238 on the mass 237). A typical instrument would have 230 mmradius of curvature, single or double focussing, and single or multiple filament design. The pressure in the ionization chambershould be below 3 100.4 mPa

25、6 torr (typically 100.0137 torr).mPa).8.2 Preconditioning Unit for the TIMSTo dry filament after deposition of uranyl solution.8.3 Rhenium Filament Loading Assembly for the TIMSIn this test method, a double filament set up is used.8.4 PipetsAutomatic or equivalent, 1, 20, 50, and 100 L.8.5 Pipets Ti

26、psIn accordance with 6.48.4.8.6 Liquid Dispenser2.5 mL.8.7 Disposable Polypropylene Vials.9. Reagents and Materials9.1 Purity of MaterialsReagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that allreagents conform to the specification of the Committee on A

27、nalytical Reagents of the American Chemical Society where such3 The last approved version of this historical standard is referenced on www.astm.org.4 Areduced number of detectors may be used which will correspond to a reduced number of isotopes analyzed. For single collector instruments, refer to Sp

28、ecification C696.C1413 182specifications are available.5 Other grades may be used provided it is first ascertained that the reagent is of sufficiently high priorityto permit its use without lessening the accuracy of the determination.9.2 Purity of WaterDemineralized or distilled water is found accep

29、table for this uranium isotopic analysis.9.3 High Purity Rhenium Filaments ( 99.95 %), with geometrical characteristics in accordance with the TIMS manufacturersrecommendations (typically thickness is 0.04 mm and width is 0.70 mm). Some equipment may accept tungsten filaments.9.4 Isotopic Uranium St

30、andardsStandards:9.4.1 UF6 of certified 236U, 235U isotopic composition, such as COG 006, 008, 009, 010, 013, 014, 015.69.4.2 U3O8 of certified isotopic composition, such as NBL CRM U-010, U-020, U-030, U-050, CEA 014.79.4.3 U3O8 from reprocessed origin and of certified 236U composition, such as MIR

31、 1.79.5 Hydrofluoric Acid (0.05 M)Dilute 173 L of HF solution (sp gr 1.18, 28.9 M) to 100 mL with water.9.6 Nitric Acid (0.1 M)Dilute 0.6 mL of concentrated HNO3 (sp gr 1.42, 16 M) to 100 mL with water.10. Preparation of Apparatus10.1 Prepare the thermal ionization mass spectrometer in accordance wi

32、th the manufacturers recommendations. A verificationof collector yield and an optimisation of the ion beam may be necessary on a daily basis. This can be achieved by heating theionizing filament, locating the 187Re peak and focusing for maximum intensity. The 187Re signal is normally above 0.1 to 0.

33、2 1011 A.10.2 A verification of mass calibration is usually performed on a weekly basis in order to optimize the value for the magneticfield.11. Calibration and Standardization11.1 Because of mass segregation during the evaporation of uranium, it is necessary to adjust the ion acquisition time progr

34、amwith the analysis of uranium standards. The number of standards and the range covered will depend on the instrument used, theevaporation sequence, and the accuracy which is required.11.1.1 For the analysis of 235U in the 0.1 to 5.0 mass % range and of 234U in the 0.0055 to 0.05 mass % range, four

35、to sevenstandards should be used (see Table 1). For analysis of 236U in the 0.0003 to 0.5 mass % range, only two standards were used.11.2 Preparation of the StandardsSeparate calibrations are required for uranyl fluoride solutions and uranyl nitrate solutions.11.2.1 Uranyl Fluoride Calibration:11.2.

36、1.1 UF6 StandardsGeneral principles for hydrolysis of UF6 are described in Test Methods C761 and Practice C1346.Hydrolysis should be done in pure water (no HNO3 added). Final concentration is for example 266 g uranium per litre (20 % massU).NOTE 1Other concentrations may be used (for example, 10 % m

37、ass U), provided that volumes in 10.212.2 are adapted to deposit the same uraniumamount on the rhenium filament.NOTE 22 g of uranium are deposited on the filaments. In case of other filament geometries (see 7.39.3), other uranium amounts may be more adapted(up to 10 g U).11.2.1.2 In a polypropylene

38、vial, pour 2.5 mL of water and add 20 L of solution prepared in 9.2.1.111.2.1.1. Mix the vialcontent by inverting vigorously to obtain a solution containing approximately 2 g/L uranium.11.2.1.3 Other StandardsUranium standard solutions, if not from hydrolyzed UF6 origin, must be transformed to a pur

39、e uranylfluoride solution prior to the analysis. Dissolution of the uranic material can be performed in accordance with Practice C1347. Thesolution is then transferred in a platinum crucible to be carefully dried on a heated plate to be transformed to UO3. The residueis then dissolved with diluted H

40、F (0.05 M) to obtain an uranyl fluoride solution with an uranium concentration of 2 g/L and afluoride concentration 1 g/L.11.2.2 Uranyl Nitrate Calibration:11.2.2.1 U3O8 StandardsThe standards are dissolved in accordance with Practice C1347. The solutions are evaporated todryness and the residue is

41、transformed by calcination to U3O8. It is then dissolved in 0.1 M HNO3 to give a solution containing2 g/L uranium.11.2.2.2 Hydrolyzed UF6 StandardsUranyl fluoride solutions with an uranium concentration of 2 g/L are evaporated todryness and dissolved in 0.1 M HNO3 to give an uranyl nitrate solution

42、containing 2 g/L uranium.11.3 Analysis of the uranyl fluoride or uranyl nitrate standard solutions is performed in accordance with 10.212.2 10.412.4.5 Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washington, DC. For suggestions on the testing of reagents no

43、t listed bythe American Chemical Society, see Analar Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and NationalFormulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.6 COGEMA/Service Laboratoire, BP 16, Orano/Dpartement Laboratoir

44、es, BP16, 26701 Pierrelatte Cedex, France.7 CEA/CETAMA, BP 171, 30 207 Bagnols sur Cze, France.C1413 18311.3.1 Calibrate the TIMS in accordance with the manufacturers recommendations to achieve the users performance andquality assurance criteria.11.3.2 The 235U/238U mass discrimination factor, B, is

45、 calculated as follows:B 51/M!R/Rs!21# (1)where:B = mass discrimination factor,M = mass difference = (238-235) = 3,Rs = certified value of 235U/238U of standard, andR = average measured value of 235U/238U for n different analyses.11.3.2.1 B should be below 2 104.11.4 For each batch of routine sample

46、s to be analyzed, a verification of the calibration of the acquisition program isrecommended. This is done by inserting in the batch a standard with isotopic composition close to that of the samples.12. Procedure12.1 Prepare the solution to be analyzed in accordance with 9.211.2 to obtain either a f

47、luoride or nitrate solution with an uraniumconcentration of approximately 2 g/L.12.2 Load 1 Lof solution 10.112.1 on the filament. Dry and bake the filament with the TIMS preconditioning unit. The heatingsequence (electrical current, time applied) must be performed in accordance with the manufacture

48、rs recommendation or usersexperience.NOTE 3For uranyl fluoride solutions, temperatures significantly greater than 600C must be avoided. The temperature of the filament during the finalstages of sample mounting is a critical parameter and can produce a significant bias between runs if not carefully c

49、ontrolled.TABLE 1 Mass Ratios to Total Uranium235U/U (mass fraction, %)Reference Certified ValuesA Summary Statistics of MeasuredValuesx sx x s nCOG 006 0.7112 0.0002 0.7110 0.0004 5COG 008 0.8676 0.0008 0.8670 0.0004 20NBL CRM U010 0.9911 0.0005 0.9918 0.0009 50COG 009 1.0705 0.0010 1.0696 0.0005 5COG 010 1.3006 0.0012 1.2995 0.0004 10NBL U020 2.0130 0.001 2.0131 0.0009 18COG 013 2.5959 0.0026 2.5969 0.0005 10NBL U030 3.0032 0.0008 3.0042 0.0014 26COG 014 3.3678 0.0034 3.3663 0.0006 20CEA 014 3.36