ASTM C1343-2011 Standard Test Method for Determination of Low Concentrations of Uranium in Oils and Organic Liquids by X-ray Fluorescence《油和有机溶液中铀的底浓度的标准试验方法》.pdf

《ASTM C1343-2011 Standard Test Method for Determination of Low Concentrations of Uranium in Oils and Organic Liquids by X-ray Fluorescence《油和有机溶液中铀的底浓度的标准试验方法》.pdf》由会员分享，可在线阅读，更多相关《ASTM C1343-2011 Standard Test Method for Determination of Low Concentrations of Uranium in Oils and Organic Liquids by X-ray Fluorescence《油和有机溶液中铀的底浓度的标准试验方法》.pdf（5页珍藏版）》请在麦多课文档分享上搜索。

1、Designation: C1343 11Standard Test Method forDetermination of Low Concentrations of Uranium in Oilsand Organic Liquids by X-ray Fluorescence1This standard is issued under the fixed designation C1343; the number immediately following the designation indicates the year oforiginal adoption or, in the c

2、ase 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 fluo

3、rescence (XRF) of oilsand organic solutions containing uranium. Two different prepa-ration techniques are described.1.2 The procedure is valid for those solutions containing 20to 2000 g uranium per mLas presented to the spectrometer forthe solution technique and 200 to 50 000 g uranium per g forthe

4、pellet technique.1.3 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 or that this contamination, whenever present, has beencorrected for mathematically. Such corrections

5、 are not ad-dressed in this procedure. Care must be taken that the internalstandard and sample medium are compatible; that is, samplesmust be miscible with tri-n-butyl phosphate (TBP) and mustnot remove the internal standard from solution.Alternatively, ascatter line may be used as the internal stan

6、dard.21.4 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.5 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 establi

7、sh appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. Specific precau-tionary statements are given in Section 9 and Note 2.2. Referenced Documents2.1 ASTM Standards:3C1110 Practice for Sample Preparation for X-Ray EmissionSpectrometric A

8、nalysis of Uranium in Ores Using theGlass Fusion or Pressed Powder MethodC1254 Test Method for Determination of Uranium in Min-eral Acids by X-Ray FluorescenceD1193 Specification for Reagent WaterE135 Terminology Relating to Analytical Chemistry forMetals, Ores, and Related Materials2.2 NIST Documen

9、t:ANSI/HPS N43.22001 Radiation Safety for X-ray Diffrac-tion and X-ray Fluorescence Analysis Equipment43. Terminology3.1 DefinitionsSee definitions in Terminology E135.4. Summary of Test Method4.1 Solution standards containing 20 g uranium per mL to2000 g uranium per mL or pellet standards containin

10、g 200 to50 000 g uranium per g and an internal standard are placed ina liquid sample holder of an X-ray spectrometer and exposed toan X-ray beam capable of exciting the uranium L-a emissionline and the appropriate internal standard line. The intensitiesgenerated are measured by an appropriate detect

11、or. The inten-sity ratio values obtained from these data are used to calibratethe X-ray analyzer. Samples are prepared having a similarmatrix to fit the calibration range and measured using the sameanalytical parameters.NOTE 1Yttrium, strontium, and bromine K-a and thorium L-a lineshave been used su

12、ccessfully as internal standard lines. Explanation of theinternal standard method of analysis is outside the scope of this testmethod and is found in several sources.5,65. Significance and Use5.1 This test method is applicable to organic solutionscontaining 20 to 2000 g uranium per mL of solution pr

13、esented1This 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 Feb. 1, 2011. Published February 2011. Originallyapproved in 1996. Last previous edition approved in 2007 as

14、 C134396(2007). DOI:10.1520/C1343-11.2Andermann, G., and Kemp, J. W., “Scattered X-rays as Internal Standards inX-ray Spectroscopy,” Analytical Chemistry, Vol 20, No. 8, 1958.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For

15、 Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.4Available from U.S. Department of Commerce, National Institute of Standardsand Technology, Gaithersburg, MD 20899.5Bertin, E. P., Introduction to X-ray Spectrometric Analysis, Plenum Pr

16、ess, NewYork and London, 1978.6Tertian, R., and Claisse, F., Principles of Quantitative X-ray FluorescenceAnalysis, Heyden such cups decrease the likelihood of contamination of thesamples.7.2.2 Polyester, polyethylene, and polypropylene films havebeen used successfully as the film window for such cu

17、ps. Testsshould be performed to determine the serviceability of any filmchosen before the insertion of samples into the instrument.7.3 Solution Dispenser (Optional)If used, the solutiondispenser for the internal standard solution should be capableof dispensing the internal standard reproducibly to a

18、 level of0.5 % relative standard deviation of the volume dispensed.7.4 Fusion Cruciblesgraphite or platinum are acceptable;platinum is recommended.8. Reagents and Materials8.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reag

19、ents conform to the specifications of the Committee onAnalytical Reagents of the American Chemical Society wheresuch specifications are available.7Other grades may be used,provided it is first ascertained that the reagent is of sufficientlyhigh purity to permit its use without lessening the accuracy

20、 ofthe determination.8.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean reagent water in con-formance with Specification D1193.8.3 Nitric Acid, HNO3,concentrated (70 %).8.4 1,3,5-Tribromobenzene, technical grade (or substitutefor internal standard).8.5 Tri-

21、n-Butyl Phosphate (TBP), technical grade.8.6 Uranium Oxide,U3O8, NBL CRM 129,8or equivalent.8.7 Lithium Tetraborate,Li2B4O7or LiTB, technical grade,fused and ground (or other fusion flux material).8.8 Yttrium Oxide,Y2O3, spectrographically pure (or suit-able internal standard substitute).9. Technica

22、l Precautions9.1 X-ray fluorescence equipment analyzes by the interac-tion of ionizing radiation with the sample. Applicable safetyregulations and standard operating procedures must be re-viewed prior to the use of such equipment. All current XRFspectrometers are equipped with safety interlock to pr

23、eventaccidental penetration of the X-ray beam by the user. Do notoverride these interlocks (see ANSI/HPS N43.22001).9.2 Instrument performance may be influenced by environ-mental factors such as heat, vibration, humidity, dust, strayelectronic noise, and line voltage stability. These factors andperf

24、ormance characteristics should be reviewed prior to the useof this test method.10. Preparation of Apparatus10.1 Chamber EnvironmentThe standards and samplesused in this test method are corrosive liquids. Some fumes willbe emitted from the sample cups. These fumes may bedetrimental to the spectromete

25、r chamber. It is desirable to flushthis chamber with an inert gas (usually helium) before andduring analysis. Some X-ray spectrometers control the changeof sample chamber environment (air, vacuum, and helium)automatically through the software; in others, it must be donemanually. Follow the instrumen

26、t manufacturers recommenda-tions to achieve the inert gas environment.NOTE 2Caution: Allow sufficient stabilization time before analysis.Care must be taken to ensure that a vacuum environment is not chosenwith liquid samples. Standards and samples must be counted in sameenvironment.10.2 X-ray Power

27、SupplyIf the power to the X-ray tube isnot controlled by the instrument software, set the propercombination of voltage and current for the instrument in use.These settings must be ascertained by the user for his instru-ment and choice of X-ray tube. Rhodium, gold, tungsten, andmolybdenum target X-ra

28、y tubes have been used successfullyfor this analysis. Allow sufficient stabilization time prior toanalysis.11. Calibration and Standardization11.1 Solution Technique11.1.1 Internal Standard Solution:11.1.1.1 Weigh 65.64 g of 1,3,5-tribromobenzene to thenearest 0.1 mg. Transfer the material to a 400-

29、mL beaker; add200 mL of TBP.11.1.1.2 Dissolve the material in TBP; heat on a hot plate, ifnecessary.11.1.1.3 Transfer the dissolved material to a 1000-mLvolumetric flask, and dilute to volume with TBP. (Storage ofthe solution in an opaque container with a screw cap isrecommended.)7Reagent Chemicals,

30、 American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Form

31、ulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.8Available from U.S. Department of Energy, New Brunswick Laboratory, D350,9800 South Cass Avenue, Argonne, IL 60439, Attn: Reference Material Sales.C1343 11211.1.2 “Master” Standards:NOTE 3Because of the difficulty of accurately weighin

32、g the smallamounts of uranium oxide necessary for low-concentration standards,calibration standards are made by dilution from “master” standards. Thetotal volume of the standard prepared may be adjusted to meet the usersanalytical throughput if the weights are adjusted appropriately.11.1.2.1 Prepare

33、 the standards at each desired concentrationlevel by weighing the quantities of uranium oxide given inTable 1 into 400-mL beakers.11.1.2.2 Dissolve the oxide in 50 mL of water and 10 mL ofconcentrated nitric acid. Evaporate the solution to near drynessor to a syrupy solution.11.1.2.3 Add enough TBP

34、to bring the uranium back intosolution. (Keep the volume below 200 mL.)11.1.2.4 Transfer the solution to a 500-mL volumetric flaskusing TBP. When cool, add 1 mL of concentrated nitric acidwhile diluting to volume with TBP; cap and mix thoroughly.11.1.3 “Secondary Master” Standards:11.1.3.1 Prepare a

35、 500 g/mL standard by pipetting 25 mLof the 5000 g/mL“master” standard into a 250-mLvolumetricflask. Dilute to volume with TBP, and mix thoroughly.11.1.3.2 Prepare a 100 g/mL standard by pipetting 25 mLof the 1000 g/mL“master” standard into a 250-mLvolumetricflask. Dilute to volume with TBP, and mix

36、 thoroughly.11.1.4 Calibration Standards:11.1.4.1 Prepare the calibration standards by pipetting intolabeled 50-mL volumetric flasks the amounts of each “master”standard given in Table 2.11.1.4.2 Add 2 mL of the internal standard to each flask.Dilute to volume with TBP, and mix thoroughly.NOTE 4The

37、internal standard solution may be added using anautomatic dispenser or dispensing pipette. However, care must be taken toensure that no adjustment to the dispenser is made between use forstandards and use for samples.11.2 Pellet Technique11.2.1 Internal Standard Solution (25.0 g/L):11.2.1.1 Prepare

38、the internal standard solution as describedin the Calibration heatingrates and cooling rates may vary and cause cracking or poor crystallizationof melt. Remelting in same crucible does not invalidate the analysis.11.3 Instrument Calibration:NOTE 6The frequency of calibration, use of blanks, spikes a

39、ndduplicates, labeling, and length of storage of solutions shall be inaccordance with the users quality assurance/quality control plan andrequirements.11.3.1 Follow the manufacturers instructions for the instru-ment in use to obtain intensity data for the uranium L-a and theinternal standard line fo

40、r each standard.11.3.2 Care must be exercised that the analytical conditionsdetermined appropriate for the instrument in use are docu-mented, or recorded, in sufficient detail that these may bereproduced in subsequent runs and when analyzing thesamples.11.3.3 Calculate the uranium/internal standard

41、ratios fromthe data obtained in 11.3.1. Calculate a calibration curve usingthese ratios. The curve should be at least a second orderpolynomial (quadratic) or should have a term to correct foruranium self-absorption. Both have been found acceptable.Currently available instrument software would contai

42、n one orthe other, or perhaps both. (A complete discussion of themathematical derivation of the following equations is outsidethe scope of this test method. Explanations of correctionmodels and interelement effects are found in severalsources.5,6) The quadratic equation will have the formY 5 CX21 BX

43、 1 A (1)where:Y = concentration of uranium,X = uranium/internal standard intensity ratio, andA,B,C = coefficients of quadratic equation.11.3.4 For self-absorption, the equation will have the formY 5 MX 1 B!1 1aX/100! (2)TABLE 1 “Master” Standards for Uranium in Organic LiquidsUranium Oxide, gAConcen

44、tration, g U/mL2.9490 50000.5898 1000AThe weight of uranium oxide is based on the value of NBL CRM 129. Weightswill need to be adjusted for the purity of the uranium reference material used.Follow instructions on the certificate accompanying the material for drying andpurity correction, where applic

45、able.TABLE 2 Calibration Standards for Uranium in Organic Liquids“Master” Standard Used,g U/mL“Master” StandardPipetted, mLCalibration StandardConcentration, g U/mL5000 20 20005000 15 15005000 10 10001000 25 500500 25 250500 10 100100 25 50100 10 20C1343 113where:Y = concentration of uranium,X = ura

46、nium/internal standard intensity ratio,M = slope of straight line,B = intercept of straight line, anda = self-absorption coefficient.NOTE 7Units used for Y in Eq 1 and Eq 2 may be changed, asappropriate, for the software in use.12. ProcedureNOTE 8Some estimate of the approximate g U/L will be necess

47、ary todetermine the appropriate dilution. This may be obtained by gammacounting of the incoming sample, prior knowledge of the origin of thesample, or some other scheme devised by the user. Such schemes areoutside the scope of this test method.12.1 Sample Preparation:12.1.1 Solution Technique12.1.1.

48、1 Shake the sample and pipet an appropriate amountinto a tared 50-mL volumetric flask.NOTE 9Some estimate of the approximate g U/L will be necessary todetermine the appropriate dilution. This may be obtained by gammacounting of the incoming sample, prior knowledge of the origin of thesample, or some

49、 other scheme devised by the user. Such schemes areoutside the scope of this test method.12.1.1.2 Obtain the gross weight of the sample and flask.(This may be omitted if an answer on a weight basis is notdesired.)12.1.1.3 Add 2 mL of the internal standard solution; diluteto volume with TBP and mix thoroughly.12.1.2 Pellet Technique12.1.2.1 Weigh 15.00 6 0.03 g LiTB into a labeled cruciblefor each test sample desired.12.1.2.2 Shake the sample to homogenize contents. Forextremely thick or viscous samples, stirring with a glass rodmay be the best opti