1、Designation: C 1517 02Standard Test Method forDetermination of Metallic Impurities in Uranium Metal orCompounds by DC-Arc Emission Spectroscopy1This standard is issued under the fixed designation C 1517; the number immediately following the designation indicates the year oforiginal adoption or, in t
2、he 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 test method describes the steps necessary for thepreparation and determination
3、of impurity metals in uraniummetal and uranium compounds by DC arc emission spectros-copy.1.2 The method is valid for those materials that can bedissolved in acid and/or converted to an oxide in a mufflefurnace (see Practice C 1347).1.3 This method uses the carrier distillation technique toselective
4、ly carry the impurities into the arc, leaving theuranium oxide in the electrode. If it is necessary to determinethe carrier metal(usually a silver or strontium, or galliumcompound) as an impurity, another technique must be chosenfor that element.1.4 This standard may involve hazardous materials, ope
5、ra-tions and equipment. This standard does not purport to addressall of the safety concerns, if any, associated with its use. It isthe responsibility of the user of this standard to establishappropriate safety and health practices and determine theapplicability of regulatory limitations prior to use
6、.2. Referenced Documents2.1 ASTM Standards:C 753 Specification for Nuclear Grade, Sinterable UraniumDioxide Pellets2C 761 Test Methods for Chemical, Mass Spectrometric,Spectrochemical, Nuclear, and Radiochemical Analysis ofUranium Hexafluoride2C 776 Specification for Sintered Uranium Dioxide Pellets
7、2C 788 Specification for Nuclear Grade Uranyl Nitrate So-lutions2C 859 Terminology Relating to Nuclear Materials2C 967 Specification for Uranium Ore Concentrate2C 1347 Practice for Preparation and Dissolution of UraniumMaterials for Analysis2E 115 Practice for Photographic Processing in OpticalEmiss
8、ion Spectrographic Analysis3E 116 Practice for Photographic Photometry in Spectro-chemical Analysis3E 130 Practice for Designation of Shapes and Sizes ofGraphite Electrode3E 135 Terminology Relating to Analytical Chemistry forMetals, Ores and Related Materials3E 402 Test Method for Spectrographic An
9、alysis of UraniumOxide (U3O8) by Gallium Oxide Carrier Technique43. Terminology3.1 See definitions and terms in Terminologies C 859 andE 135.4. Summary of Test Method4.1 Uranium metal, solutions and compounds are convertedto uranium oxide (U3O8) in a muffle furnace. A weighedamount of the oxide is m
10、ixed with an appropriate spectro-graphic carrier and loaded into a graphite electrode. Theelectrode is excited in a DC arc and the light is dispersed by aspectrograph or spectrometer. The resulting spectrum is mea-sured electronically or photographed on photographic plates orfilm sensitive to the pr
11、oper regions. The line intensities arecompared directly to standard plates or to calibration curvesderived from the arced standards.5. Significance and Use5.1 This test method is applicable to uranium metal, ura-nium oxides and compounds soluble in nitric or sulfuric acid,and uranium solutions which
12、 can be converted to uraniumoxide (U3O8) in a muffle furnace. It may be used to determinethe impurities in uranium compounds as listed in SpecificationsC 753, C 776, C 788, and C 967.6. Apparatus6.1 SpectrographA spectrograph with sufficient resolvingpower and linear dispersion to separate the analy
13、tical linesfrom other lines in the spectrum of the sample in the spectralregion of 230.0 to 855.0 nm is required. Instruments with areciprocal linear dispersion in the first order of 0.5 nm/mm or1This test method is under the jurisdiction of ASTM Committee C26 on NuclearFuel Cycle and is the direct
14、responsibility of Subcommittee C26.05 on TestMethods.Current edition approved Jan. 10, 2002. Published May 2002.2Annual Book of ASTM Standards, Vol 12.01.3Annual Book of ASTM Standards, Vol 03.05.4Annual Book of ASTM Standards, Vol 03.06.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C
15、700, West Conshohocken, PA 19428-2959, United States.less are satisfactory. A direct-reading spectrometer of compa-rable quality may be substituted for equipment listed, in whichcase the directions given by the manufacturer should besubstituted for those in this procedure.6.2 Excitation SourceUse an
16、 arc power source capable ofproviding a dc arc of up to 14-A dc, depending on the carrierused and electrode design.6.3 Excitation StandConventional type with adjustablewater-cooled electrode holders (may be fitted with automaticsample changers if desired).6.4 Photographic Processing EquipmentUse dev
17、eloping,fixing, washing and drying equipment conforming to PracticeE 115.6.5 Microphotometer, having a precision of at least 6 1%for transmittances.6.6 Mixer, for dry materials.6.7 Platinum Crucible.6.8 Venting Tool, (see Fig. 1, Test Method E 402 or Fig. 8,Test Methods C 761).6.9 Muffle Furnace, 10
18、00C capability.7. Reagents and Materials7.1 Purity of MaterialsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents conform to the specifications of the Committee ofAnalytical Reagents of the American Chemical Society wheresuch specifications
19、 are available. Other grades may be usedprovided it is first ascertained that the reagent is of sufficientlyhigh purity to permit its use without lessening the accuracy ofthe determination.7.2 ElectrodesThe anode and counter electrodes shouldbe of the S-2, S 16 and C-1 types as given in Practice E 1
20、30 (orequivalent).NOTE 1Exact shapes and dimensions of the electrodes are not ascritical as given in Practice E 130; however, dimensions of the electrodesused should be consistent and it is essential that the same dimensionelectrodes be used for standards and samples.7.3 Photographic Processing Solu
21、tionsPrepare solutionsas noted in Practice E 115.7.4 Photographic Film/PlatesUse photo emulsion SA-1and 1-N or equivalent.7.5 Powder Paper.7.6 Nitric Acid (HNO3)concentrated (70 %), electronicgrade, or equivalent.7.7 Sulfuric Acid (H2SO4)concentrated, electronic grade,or equivalent.7.8 Spectrographi
22、c CarrierThe following spectrographiccarriers have been used successfully for DC Arc analysis:7.8.1 Silver Chloride-Lithium Fluoride, 11:1 w/w ratio.7.8.2 Silver Chloride-Silver Fluoride, 4:1 w/w ratio.7.8.3 Gallium Oxide, 99.99 % or better.7.8.4 Silver Chloride-Strontium Fluoride, 16.4 mol % SrF2in
23、 AgCl.7.8.5 Gallium Oxide-Lithium Fluoride, 11:1 w/w ratio.7.9 Mixing Vial, plastic, 12.7 mm (1/2 in.) by 25.4 mm (1in.) with cap and 10 mm (3/8 in.) plastic mixing bead.7.10 Standard Uranium Oxide (U3O8) DiluentUse NBLCRM 1294(or its replacement or equivalent) of known impu-rity level as a diluent.
24、8. Precautions8.1 Consult manufacturers Material Safety Data Sheets(MSDS) for chemical incompatibilities, specific hazards, orspill cleanup for any hazardous materials used in this method.8.2 All mixing and weighing operations involving uraniumoxides should be carried out in properly functioning hoo
25、ds orexhaust boxes.9. Standardization and Calibration9.1 Standards:9.1.1 Standards may be synthesized by adding the impurityelements to purified U3O8(NBL CRM 1295, or equivalent) andhomogenizing. Impurities in powder form, preferably as ox-ides, may be blended in U3O8; impurities in solution may bea
26、dded to U3O8and the mixture dried, blended and reignited, orthe impurities and uranium may be combined in solution andreconverted to U3O8. The individual elements should grade insuch a ratio as to facilitate visual comparisons covering thedesired analytical range for each.9.1.2 The compounds used to
27、 make U3O8impurity stan-dards should be of the highest purity available.9.1.3 Alternatively, commercially available uranium impu-rity standards, such as NBL CRM 1235and 1245seriesstandards, may be used. (Other standards may be available; theuser should determine quality and/or applicability prior to
28、 use.)These may be supplemented by synthetic standards to extendcalibration ranges, if necessary.9.1.4 For each standard used, prepare in the same ratio ofuranium oxide to carrier as for samples (see Table 1 for furtherdetails).9.1.5 Charge the electrode and arc at the same conditions asdetermined t
29、o be optimum for the instrument in use.9.2 Calibration Curves:9.2.1 If a microphotometer is used, determine emulsioncalibration curves and analytical curves as described in Prac-tice E 116.9.2.2 If a direct reading spectrograph is used, calibrateaccording to manufacturers instruction.5Available from
30、 the US Department of Energy, New Brunswick Laboratory, D350, 9800 South Cass Avenue, Argonne, IL 60439, ATTN: Reference Material Sales.TABLE 1 CarrierSample CombinationsCarrierMaterialCarrier Wt,(mg)Oxide Wt,(mg)ElectrodeCharge, (mg)Mixing Time,(s)AgCl/AgF(4:1)50 250 50 180AgCl/LiF(11:1)30 270 100
31、60AgCl/SrF2(6:1)50 450 100 30Ga2O3/LiF(11:1)20 380 100 25Ga2O3A7 343 100 60AFor the determination of Ag and Li only.NOTEThe above listed combinations of carrier, uranium oxide andelectrode charge have been successfully used for the determination ofimpurities in uranium oxide. Other combinations may
32、be available orsuitable. However, the user must demonstrate comparable precision andbias.C 151729.2.3 For visual comparison, the darkness/width of eachstandard and impurity element line will establish the individualanalyte concentrations.10. Procedure10.1 Sample Preparation10.1.1 Liquid Samples:10.1
33、.1.1 Transfer into a platinum crucible a sufficientamount of liquid to yield not more than 2 g uranium oxide.10.1.1.2 Place the crucible on a hot plate and evaporate todryness. Do not allow to boil.NOTE 2The addition of H2SO4may be necessary for solutions ofuranyl chloride to effect complete convers
34、ion to oxide.10.1.1.3 Continue the preparation at 10.1.2.2.10.1.2 Miscellaneous Uranium Oxides, Solids or Com-pounds:10.1.2.1 Transfer not more than2goftheuranium com-pound to a platinum crucible.10.1.2.2 Place in a cool muffle and set the muffle to 900 650C.NOTE 3Some impurities (for example, Mo, W
35、, Cr) may be lost at hightemperatures. Do NOT place samples directly in hot muffle. Lowertemperatures may be used if it is determined that complete oxideconversion is achieved.10.1.2.3 Leave the crucibles and samples in the muffle untilconversion to U3O8is complete.NOTE 4Times will vary depending on
36、 amount and type of sample; theuser must determine optimum time experimentally for his sample types.10.2 Addition of Carrier:10.2.1 Weigh an appropriate amount of uranium oxide intoa mixing vial and add the amount of carrier chosen (see Table1).10.2.2 Mix on a mixer for 1 to 3 min.NOTE 5Exact time w
37、ill depend on efficiency of mixing action of themixer chosen, the amount of sample and carrier used. The user mustdetermine this experimentally for his sample type (see Table 1).10.3 Charge each electrode with the amount of uraniumoxide and carrier determined to be optimum. For each samplecharge dup
38、licate electrodes.10.4 Grip each electrode with forceps and pack the chargeby tapping on a solid surface.10.5 Further compress and vent the charge with the ventingtool shortly before arcing the samples. Wipe the venting toolwith tissue between different samples.NOTE 6Venting is dependent on the carr
39、ier used and may not berequired. A combination tamping/venting tool is permissible.10.6 Arc the electrodes at the conditions determined opti-mum for the instrument in use.10.7 If photographic film or plates are used, process asdirected in Practice E 115. If a direct reading spectrograph isused, the
40、impurity values will be reported as each electrode isarced.10.8 Determine each impurity by comparing the lines foreach element using the calibration curves established in 9.2.11. Precision and Bias11.1 There are not certified materials for the determinationof all elements that may be analyzed by thi
41、s method. Norwould all the elements be expected in these materials. How-ever, there are standards available from the New BrunswickLaboratory certified for many of the elements of interest. Datausing these standards and other available standards are listed inTables 3 and 4. Each user must determine t
42、he proper qualitycontrol and assurance measures for his application and thecarrier/sample combination used. For different elements therelative standard deviation was found to be between 9 % andTABLE 2 Typical Wavelengths and Limits of DetectionElement Wavelength(nm)LOD usingAgCl/AgF(ppm)LOD usingAgC
43、l/LiF(ppm)LOD usingGa2O3/LiF(ppm)Al 308.21236.70151As 234.98 10 . . .Au 267.59 1 . . .B 249.77 0.1 0.4 0.5Ba 455.40493.4121Be 234.86249.450.111Bi 306.77 1 . . .Ca 396.84422.641025Cd 228.80 0.1 0.3 0.5Co 240.72340.5115Cr 284.33425.44427.482103Cs 852.11 10 . . .Cu 324.75327.40121Fe 248.33252.28302.061
44、0202Ga 294.36 1 . . .Ge 265.12 1 . . .K 769.89 10 . . .Li 670.78 0.2Mg 279.55280.272101Mn 279.48279.831101Mo 313.21 10Na 588.99589.59110Nb 316.34 10 . . .Ni 300.25341.48152P 255.33213.6210025Pb 283.31 4 3 1Pd 340.46 1 . . .Rb 780.02 20 . . .Sb 259.81 2 10Si 250.69251.61288.1610101Sn 283.99317.501021
45、Sr 407.77 20 . . .Ta 265.33 35Ti 334.90337.2845V 292.40318.3415W 294.70 100 . . .Zn 330.25213.86101030C 1517323 %. These sigma are an indication of precision. The relativedifference from the certified values vary from 0 % to 20 %.These numbers are an indication of the potential bias. This datawas co
46、llected over a 12-month period in two different labora-tories by several different technicians and is typical of data forthese techniques. Relative standard deviations are calculatedrelative to average value. For other elements not in thesestandards, the precision is normally 50 % to +100 % of thede
47、termined value (Test Method E 402). The user can expectprecision and bias values for some elements (those with weakemission lines or highly refractory elements) to be greater thanthe values listed in Tables 3 and 4. Those values must bedetermined by the user.12. Keywords12.1 carrier distillation; dc
48、-arc; emission spectroscopy; im-purities in uraniumASTM 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 righ
49、ts, and the riskof infringement 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 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 hav
