ASTM C1508-2001(2006) Standard Test Method for Determination of Bromine and Chlorine in UF6 and Uranyl Nitrate by X-Ray Fluorescence (XRF) Spectroscopy《用X射线荧光光谱测定法UF-6和硝酸铀酰中溴和氯的含量的.pdf

1、Designation: C 1508 01 (Reapproved 2006)Standard Test Method forDetermination of Bromine and Chlorine in UF6and UranylNitrate by X-Ray Fluorescence (XRF) Spectroscopy1This standard is issued under the fixed designation C 1508; the number immediately following the designation indicates the year ofori

2、ginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This method covers the determination of bromine (Br)and chlor

3、ine (Cl) in uranium hexafluoride (UF6) and uranylnitrate solution. The method as written covers the determina-tion of bromine in UF6over the concentration range of 0.2 to8 g/g, uranium basis. The chlorine in UF6can be determinedover the range of 4 to 160 g/g, uranium basis. Higherconcentrations may

4、be covered by appropriate dilutions. Thedetection limit for Br is 0.2 g/g uranium basis and for Cl is 4g/g uranium basis.1.2 This standard may involve hazardous materials, opera-tions and equipment. This standard does not purport to addressall of the safety concerns, if any, associated with its use.

5、 It isthe responsibility of the user of this standard to establishappropriate safety and health practices and determine theapplicability of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C 761 Test Methods for Chemical, Mass Spectrometric,Spectrochemical, Nuclear, and

6、 Radiochemical Analysis ofUranium HexafluorideC 787 Specification for Uranium Hexafluoride for Enrich-mentC 788 Specification for Nuclear-Grade Uranyl Nitrate So-lution or CrystalsC 1118 Guide for Selecting Components for Wavelength-Dispersive X-Ray Fluorescence (XRF) SystemsD 1193 Specification for

7、 Reagent Water3. Summary of Test Method3.1 A sample of hydrolyzed UF6(uranyl fluoride) or uranylnitrate solution is treated with sodium nitrite to reduce oxidizedforms of bromine and chlorine (bromates and chlorates) to theirrespective halide ions.Addition of silver nitrate precipitates thesilver ha

8、lides. Spike recoveries can be improved by theaddition of potassium iodide causing coprecipitation of thehalides. The halides are collected on filter paper and areanalyzed by X-ray fluorescence using two different crystal/detector systems.4. Significance and Use4.1 The method is designed to show whe

9、ther or not thetested materials meet the specifications as given in Specifica-tions C 787 and C 788.5. Interferences5.1 Plastic equipment must be used throughout the methodfor uranyl fluoride as the hydrofluoric acid in the uranylfluoride leaches chloride from glassware causing a high bias.5.2 Low r

10、ecoveries may occur as the precipitate can bedifficult to transfer quantitatively to the filter paper. A surfac-tant can be added (optional step) to minimize the adhesion ofthe precipitate to the walls of the beakers and the funnel.6. Apparatus6.1 X-Ray Spectrometer, see Guide C 1118 for the selecti

11、onof the X-ray Spectrometer.6.2 Plastic Vacuum Filtration Apparatus, for 47 mm diam-eter filter paper.6.3 Filter Paper, 0.45 micron, 47 mm diameter.36.4 Beakers, polypropylene, 250 mL.6.5 Stirring Rods, plastic or Teflon.6.6 X-ray Sample Support, Rings. Inner diameter approxi-mately 40 mm.7. Reagent

12、s7.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents conform to the specifications of the Committee onAnalytical Reagents of the American Chemical Society, where1This test method is under the jurisdiction of ASTM Commit

13、tee C26 on NuclearFuel Cycle and is the direct responsibility of Subcommittee C26.05 on Methods ofTest.Current edition approved July 1, 2006. Published September 2006. Originallyapproved in 2001. Last previous edition approved in 2001 as C 150801.2For referenced ASTM standards, visit the ASTM websit

14、e, 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.3The filter must be Cl and Br free. Millipore membrane filter type HABP() has been successfully used. An alternate

15、 is 15A from S.C.B,BP6, RN86, 07130 Soyons France. Any other equivalent is acceptable.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.such specifications are available.4Other grades may be used,provided it is first ascertained that t

16、he reagent is of sufficientlyhigh purity to permit its use without lessening the accuracy ofthe determination.7.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean reagent water conformingto Specification D 1193, Type I.7.3 Ammonium Hydroxide,NH4OH, concentrat

17、ed, specificgravity 0.90.7.4 Ammonium Hydroxide Solution, 1 + 3 (3.7 M). Dilute 1part NH4OH with 3 parts water.7.5 Surfactant, bromine and chlorine free.5(Optional).7.6 Surfactant Solution, 1 + 999. Add 1 mL of surfactant toapproximately 1 litre of water. (Optional).7.7 Nitric Acid, HNO3, concentrat

18、ed, specific gravity 1.42.7.8 Nitric Acid Solution, 1 + 999 (0.016 M). Add 1 mL ofconcentrated HNO3to approximately 200 mL of water. Add 1mL of the surfactant (7.6). (Optional). Dilute to 1 litre.7.9 Sodium Nitrite, NaNO2.7.10 Sodium Nitrite Solution, 2 g/L. Dissolve1gofsodiumnitrite in water and di

19、lute to 500 mL. Prepare fresh immedi-ately before use.7.11 Silver Nitrate, AgNO3.7.12 Silver Nitrate Solution, 2 g/L. Dissolve2gofsilvernitrate in water and dilute to 1 litre. Keep away from light in anopaque bottle. The solution should be made fresh weekly.Silver is an RCRA listed hazardous waste.

20、Make up only asmuch of this solution as required to minimize excess waste.7.13 Potassium Bromide, KBr.7.14 Bromide Solution, 500 mg Br/L. Dissolve 0.1861 g ofKBr (dried at 110C for 1 hour) in water and dilute to 250 mLin a volumetric flask.7.15 Sodium Chloride, NaCl.7.16 Sodium Chloride Solution, 10

21、00 mg Cl/L. Dissolve1.648 g NaCl (dried at 110 C for 1 hour ) in water and diluteto 1 litre in a volumetric flask.7.17 Spike Solution, 5 mg Br/L, 100 mg Cl/L. Transfer 10mL of 500 mg Br /L solution into a 1 litre volumetric flask bypipette. Transfer 100 mL of 1000 mg Cl /L into the flask bypipette.

22、Dilute to volume.7.18 Potassium Iodide, KI. (Optional).7.19 Potassium Iodide Solution, (Optional), 1g I/L. Dis-solve 0.131 g potassium iodide in water and dilute to 100 mL.The solution should be prepared weekly.8. Standard Preparation8.1 Pipette the following aliquots of spike solution (from7.17) in

23、to polypropylene beakers. 0 mL, 1 mL, 2 mL, 5 mL, 10mL. The aliquots represent 0g Br, 5g Br, 10g Br, 25g Br,50g Br and 0g Cl, 100g Cl, 200g Cl, 500g Cl, 1000g Cl.8.2 Add 70 mL water to each beaker.8.3 Follow steps 9.3-9.8 at the same time as the samples.9. Procedure9.1 Transfer a known aliquot of ur

24、anyl fluoride solution(prepared following Test Methods C 761) or uranyl nitrate thatcontains a known amount of uranium, approximately 5 g, witha plastic graduated cylinder into a polypropylene beakercontaining 70 mL water.NOTE 1Recommend cleaning all laboratory equipment with ammo-nium hydroxide sol

25、ution (7.4) prior to use.9.2 Follow laboratory QA practices and run the necessaryduplicates, spikes and controls with the samples. Use thesolution prepared in 7.17 for the spikes.NOTE 22 mL and 4 mL spike aliquots were found to be reasonablevolumes.9.3 Add 0.5 mL of potassium iodide solution to each

26、 sampleand standard. (Optional step).9.4 Add 4 mL of surfactant solution 7.6. (Optional step).9.5 Add 10 mL of sodium nitrite solution to each sampleand standard. Stir each solution with a dedicated plastic stirringrod and allow to stand for a minimum of 2 minutes.9.6 Slowly and with stirring add 25

27、 mL of the silver nitratesolution. Remove the plastic stirring rods. Heat the solution ina water bath at approximately 80C 6 10C for 112 hours.9.7 Remove from the bath. Allow the halides to precipitateovernight. A 2 hour precipitation time has been found to besuccessful, but the user must establish

28、precision and bias basedon the shorter time. The precision and bias data in this standardwere generated using an overnight precipitation.9.8 Filter using 0.45 micron filter paper. Use a plasticvacuum filtration assembly. Use a plastic rod with a rubberpoliceman to aid the transfer of precipitate to

29、the filter. Use 1+ 999 nitric acid solution to wash the precipitate. Dry the filtersbefore counting in the X-ray.9.9 Place the filters on X-ray sample support rings and tapeor glue in place.9.10 Analyze using the X-ray.10. Instrument Calibration10.1 Follow the manufacturers instructions for setting

30、upthe instrument to achieve an inert gas environment and toobtain the following instrument parameters. (See Table 1).10.2 Run the standards and construct a calibration curveusing the instruments software or by manually plotting thecurve using linear chart paper.10.3 Run the samples. Determine the we

31、ight of Br and Clpresent on the filter papers from the calibration curves.Calculate the concentration of Br and Cl in the samples byfollowing Section 11.4Reagent Chemicals, American Society Specifications, American ChemicalSociety, Washington, DC.5Triton X-100, Rohm and Haas, has been successfully u

32、sed.TABLE 1 Suggested X-Ray SettingsBromine ChlorineLine Ka KaCrystal LiF 200(Lithium fluoride)PE (Tetrakis(hydroxymethyl)-methane)Detector Scintillation FlowOrder 1 1X-ray tube Rhodium RhodiumTube voltage (kV) 45 45Tube Amperage (mA) 45 75Counting Time (s) 40 40C 1508 01 (2006)211. Calculation11.1

33、Calculate the halide content as follows:Halide, g/g uranium basis 5A 3 1000B 3 Cwhere:A = micrograms halide from the calibration curve,1000 = conversion factor, litres to millilitres,B = sample aliquot from 9.1, in millitres, andC = uranium concentration of sample solution, in g/L.12. Precision and

34、Bias12.1 Uranium Hexafluoride Data:12.1.1 Precision in UF6SamplesThe single laboratoryprecision for the average of multiple determinations is given in. The data for laboratory A were collected using a rhodiumX-ray tube and a LiF200 crystal for bromine and a PE crystalfor chlorine. Potassium iodide (

35、optional 9.3) was added to thesamples in laboratory A. The results were obtained over a 3month period by two technicians. The results for laboratory Bwas obtained by 1 technician over a 1 year period. Potassiumiodide was not added to Laboratory B samples. The precisionis given in Table 2.12.1.2 Bias

36、 in UF6SamplesNo standard material certifiedfor bromine and chlorine in UF6is available. Therefore biascannot be determined. To determine lower bound bias indica-tions uranyl fluoride solutions were spiked with NIST SRM.The uncertainty of the NIST traceable standard is less than theuncertainty of th

37、e procedure. The data for Laboratory A werecollected over a 3 month period by two technicians. Potassiumiodide was added to laboratory A samples. The result data forLaboratory B were obtained over a 1 year period by 1technician. No potassium iodide was added to laboratory Bsamples. The mean minus th

38、e prepared values are an indicationof the bias. The relative differences are given in Table 3. Therelative difference is (mean-known)/known 3 100 %.12.2 Uranyl Nitrate Data:12.2.1 Precision in Uranyl Nitrate SamplesThe resultdata were collected in 1 day by 1 technician. The precision isgiven in Tabl

39、e 4. No potassium iodide (optional 9.3) was addedto the uranyl nitrate samples.12.2.2 Bias in Uranyl Nitrate SamplesThe bias should beequivalent to the bias in UF6samples.12.3 The supporting data for Tables 2-4 are available fromASTM headquarters.13. Keywords13.1 bromine; chlorine; uranium hexafluor

40、ide; X-ray fluo-rescence; XRFTABLE 2 Within Laboratory Precision For UF6Laboratory HalideConcentration(g halide/g U)Standard Deviation(g halide/g U)Number ofDeterminationsA Bromine 0.44 0.06 10A Bromine 3.1 0.2 9B Bromine 5.1 0.7 109A Chlorine 2.4 2.1 9A Chlorine 66 6 8A Chlorine 185 19 9B Chlorine

41、48 5 107C 1508 01 (2006)3ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infring

42、ement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard

43、or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views

44、known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting

45、ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).TABLE 3 Bias Estimates For UF6Laboratory Halide Spike Concentration(g halide/g U)Spike(g halide)Mean(g halide)Bias Estimate Relative Difference Number of De

46、terminationsA Bromine 2 10 10.6 +0.6 +6 % 10A Bromine 4 20 20.5 +0.5 +2.5 % 10B Bromine 5 25 25.5 +0.5 +2 % 109A Chlorine 40 200 213 +13 +6.5 % 10A Chlorine 80 400 450 +50 +12.5 % 10B Chlorine 50 250 238 12 6 % 107TABLE 4 Within Laboratory Precision For Uranyl NitrateSolutionsHalide Concentration(g halide/g U)StandardDeviationNumber ofDeterminationsBromine 10 1.5 3Bromine Blank 0.04 3Chlorine 50 9 3Chlorine Blank 0.5 3C 1508 01 (2006)4