1、Designation: C696 11Standard Test Methods forChemical, Mass Spectrometric, and SpectrochemicalAnalysis of Nuclear-Grade Uranium Dioxide Powders andPellets1This standard is issued under the fixed designation C696; the number immediately following the designation indicates the year oforiginal adoption
2、 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 These test methods cover procedures for the chemical,mass spectrometric, and
3、 spectrochemical analysis of nuclear-grade uranium dioxide powders and pellets to determinecompliance with specifications.1.2 The analytical procedures appear in the following order:SectionsUranium by Ferrous Sulfate Reduction in PhosphoricAcid and Dichromate Titration Method2C1267 Test Method for U
4、ranium By Iron (II) Reduc-tion In Phosphoric Acid Followed By Chromium (VI)Titration In The Presence of Vanadium3Uranium and Oxygen Uranium Atomic Ratio by theIgnition (Gravimetric) Impurity Correction Method4C1453 Standard Test Method for the Determinationof Uranium by Ignition and Oxygen to Uraniu
5、m Ratio(O/U) Atomic Ratio of Nuclear Grade Uranium Diox-ide Powders and Pellets3Carbon (Total) by Direct Combustion-Thermal Con-ductivity Method2C1408 Test Method for Carbon (Total) in UraniumOxide Powders and Pellets By Direct Combustion-Infrared Detection Method3Total Chlorine and Fluorine by Pyro
6、hydrolysis Ion-Selective Electrode Method4C1502 Standard Test Method for the Determinationof Total Chlorine and Fluorine in Uranium Dioxideand Gadolinium Oxide3Moisture by the Coulometric, Electrolytic MoistureAnalyzer Method7-14Nitrogen by the Kjeldahl Method 15-22Isotopic Uranium Composition by Mu
7、ltiple-FilamentSurface Ionization Mass Spectrometric Method5Spectrochemical Determination of Trace Elements inHigh-Purity Uranium Dioxide23-30Silver, Spectrochemical Determination of, by GalliumOxideCarrier D-C Arc Technique31 and 32Rare Earths by Copper Spark-SpectrochemicalMethod2Impurity Elements
8、 by a Spark-Source Mass Spectro-graphic Method2C761 Test Method for Chemical, Mass Spectromet-ric, Spectrochemical, Nuclear, and RadiochemicalAnalysis of Uranium Hexafluoride3C1287 Test Method for Determination of ImpuritiesIn Uranium Dioxide By Inductively Coupled PlasmaMass Spectrometry3Surface Ar
9、ea by Nitrogen Absorption Method 33-39Total Gas in Reactor-Grade Uranium Dioxide Pellets2Thorium and Rare Earth Elements by Spectroscopy2Hydrogen by Inert Gas Fusion4C1457 Standard Test Method for Determination ofTotal Hydrogen Content of Uranium Oxide Powdersand Pellets by Carrier Gas Extraction3Ur
10、anium Isotopic Analysis by Mass Spectrometry2C1413 Test Method for Isotopic Analysis of Hydro-lysed Uranium Hexafluoride and Uranyl Nitrate Solu-tions By Thermal Ionization Mass Spectrometry32. Referenced Documents2.1 ASTM Standards:3C753 Specification for Nuclear-Grade, Sinterable UraniumDioxide Po
11、wderC761 Test Methods for Chemical, Mass Spectrometric,Spectrochemical, Nuclear, and Radiochemical Analysis ofUranium HexafluorideC776 Specification for Sintered Uranium Dioxide PelletsC1267 Test Method for Uranium by Iron (II) Reduction inPhosphoric Acid Followed by Chromium (VI) Titration inthe Pr
12、esence of VanadiumC1287 Test Method for Determination of Impurities inNuclear Grade Uranium Compounds by InductivelyCoupled Plasma Mass SpectrometryC1347 Practice for Preparation and Dissolution of UraniumMaterials for AnalysisC1408 Test Method for Carbon (Total) in Uranium OxidePowders and Pellets
13、By Direct Combustion-Infrared De-tection MethodC1413 Test Method for Isotopic Analysis of HydrolyzedUranium Hexafluoride and Uranyl Nitrate Solutions byThermal Ionization Mass SpectrometryC1453 Test Method for the Determination of Uranium by1These test methods are under the jurisdiction of ASTM Comm
14、ittee C26 onNuclear Fuel Cycle and are the direct responsibility of Subcommittee C26.05 onMethods of Test.Current edition approved Sept. 1, 2011. Published October 2011. Originallyapproved in 1972. Last previous edition approved in 2005 as C696 99(2005). DOI:10.1520/C0696-11.2Discontinued January 19
15、99. See C69680.3For 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.4Discontinued September 2011.5Discontinued as
16、of May 30, 1980.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Ignition and the Oxygen to Uranium (O/U) Atomic Ratioof Nuclear Grade Uranium Dioxide Powders and PelletsC1457 Test Method for Determination of Total HydrogenContent of
17、Uranium Oxide Powders and Pellets by CarrierGas ExtractionC1502 Test Method for Determination of Total Chlorineand Fluorine in Uranium Dioxide and Gadolinium OxideD1193 Specification for Reagent WaterE115 Practice for Photographic Processing in Optical Emis-sion Spectrographic Analysis6E130 Practice
18、 for Designation of Shapes and Sizes ofGraphite ElectrodesE402 Test Method for Spectrographic Analysis of UraniumOxide (U3O8) by Gallium Oxide-Carrier Technique63. Significance and Use3.1 Uranium dioxide is used as a nuclear-reactor fuel. Inorder to be suitable for this purpose, the material must me
19、etcertain criteria for uranium content, stoichiometry, isotopiccomposition, and impurity content. These test methods aredesigned to show whether or not a given material meets thespecifications for these items as described in SpecificationsC753 and C776.3.1.1 An assay is performed to determine whethe
20、r thematerial has the minimum uranium content specified on a dryweight basis.3.1.2 The stoichiometry of the oxide is useful for predictingits sintering behavior in the pellet production process.3.1.3 Determination of the isotopic content of the uraniumin the uranium dioxide powder is made to establi
21、sh whether theeffective fissile content is in compliance with the purchasersspecifications.3.1.4 Impurity content is determined to ensure that themaximum concentration limit of certain impurity elements isnot exceeded. Determination of impurities is also required forcalculation of the equivalent bor
22、on content (EBC).4. Reagents4.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are
23、 available.7Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.4.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean reagent water confor
24、mingto Specification D1193.5. Safety Precautions5.1 Proper precautions should be taken to prevent inhala-tion, or ingestion of uranium dioxide powders or dust duringgrinding or handling operations.6. Sampling6.1 Criteria for sampling this material are given in Specifi-cation C753 and Specification C
25、776.6.2 Samples can be dissolved using the appropriate disso-lution techniques described in Practice C1347, but final deter-mination of applicability must be made by the user.URANIUM BY FERROUS SULFATE REDUCTION INPHOSPHORIC ACID AND DICHROMATETITRATION METHODThis test method was withdrawn in Januar
26、y 1999 andreplaced by Test method C1267.URANIUM AND OXYGEN TO URANIUM ATOMICRATIO BY THE IGNITION (GRAVIMETRIC)IMPURITY CORRECTION METHODThis test method was withdrawn in September 2011 andreplaced by Test Method C1453.CARBON (TOTAL) BY DIRECT COMBUSTION-THERMAL CONDUCTIVITY METHODThis test method w
27、as withdrawn in January 1999 andreplaced by Test Method C1408TOTAL CHLORINE AND FLUORINE BYPYROHYDROLYSIS ION-SELECTIVE ELECTRODEMETHODThis test method was withdrawn in September 2011 andreplaced by Test Method C1502.MOISTURE BY THE COULOMETRICELECTROLYTICMOISTURE ANALYZER METHOD7. Scope7.1 This tes
28、t method covers the determination of moisture inuranium dioxide samples. Detection limits are as low as 10 g.8. Summary of Test Method8.1 The sample is heated in an oven (up to 400C) to driveoff any water. The moisture is carried from the oven into theelectrolytic cell by a flowing stream of dry nit
29、rogen. Twoparallel platinum wires wound in a helix are attached to theinner surface of the tube, the wall of which is evenly coatedwith phosphorus pentoxide (P2O5) (a strong desiccant thatbecomes electrically conductive when wet).Apotential appliedto the wires produces a measurable electrolysis curr
30、ent whenmoisture wets the desiccant. Electrolysis of the water continu-ously regenerates the cell enabling it to accept additional water.8.2 Precautions must be taken to prevent interference fromthe following sources. Hydrogen fluoride will cause permanentdamage to the cell and sample system and sho
31、uld not be rununder any conditions. Corrosive acidic gases, such as chlorineand hydrogen chloride, will corrode the instrument. Entrainedliquids and solids can cause cell failure and should beprevented from entering the gas stream. Ammonia and other6Withdrawn. The last approved version of this histo
32、rical standard is referencedon www.astm.org.7Reagent Chemicals, 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, Do
33、rset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.C696 112basic materials react with the acidic cell coating and rendersthe cell unresponsive. Hydrogen, and to a lesser extent, oxygenor air, may cause a high reading due to
34、recombination, in thecell, or in the case of hydrogen, due to reaction with oxidecoating of the sample boat to produce water. Alcohols andglycols, particularly the more volatile ones, respond like waterand therefore must not be present.9. Apparatus9.1 Moisture Analyzer, for solids, with quartz glass
35、 ovencapable of being heated from ambient temperatures to 1000C.The assembly includes electrolytic cell, flow meter, range 30 to140 cm3/min air, and a dryer assembly.89.2 Balance,9for weighing samples in the range from 1 to100 mg.9.3 Nitrogen Gas Cylinder, with a pressure regulator, a flowmeter and
36、a drying tower.10. Reagents10.1 Barium Chloride Dihydrate (BaCl22 H2O).11. Operation11.1 Turn the main power switch ON.11.2 Adjust nitrogen gas pressure to 41.4 kPa (6 psi) and theflow rate to 50 mL/min measured at the exit of the apparatus.11.3 Weigh the sample into a small, dry, aluminum boat(Note
37、 1) and insert it into the instrument oven as follows:NOTE 1For samples that have been reduced in a hydrogen atmosphereand thus contain excess hydrogen, the use of a platinum boat in place ofthe aluminum tube and nickel boat will minimize any interference due tothe hydrogen.11.3.1 Open the top of th
38、e analyzer and remove the TFE-fluorocarbon plug. Do not touch with gloves.11.3.2 With forceps pull the nickel boat one third of the wayout of the tube and place the aluminum boat and the sampleinside the nickel boat, then reposition the nickel boat near thecenter of the heating coils.11.3.3 Replace
39、the TFE-fluorocarbon plug and close the lidof the analyzer.11.4 Reset the counter to 0 g.11.5 Set the timer at 1 h.11.6 Set the temperature at 400C. This will activate theanalyzer and start the heating cycle.11.7 When the preset temperature has been reached and thecounter ceases counting, record the
40、 reading, S.12. Standardization12.1 Determine the blank by processing dry, empty, alumi-num boats according to steps 11.3-11.7 until constant valuesare obtained.12.2 Weigh and analyze replicate 5-mg samples of BaCl22H2O until consistent results are obtained. Sodium tungstatedihydrate (Na2WO42 H2O) m
41、ay also be used for calibration.13. Calculation13.1 Calculate the moisture recovery, Z, for the standard asfollows:Z 5 A 2 B!147.2Y (1)where:A = micrograms of moisture on counter when standard istested,B = micrograms of moisture on counter from blank, andY = milligrams of BaCl22 H2O. Each milligram
42、ofBaCl2H2O contains 147.2 g of water.13.2 Calculate the percent moisture in the sample as fol-lows:Moisture, % 5 S 2 B!/1000 WZ 3 100 5 S 2 B!/10 WZ (2)where:S = micrograms of moisture on counter when sample istested,B = micrograms of moisture on counter from blank,W = milligrams of sample, andZ = r
43、ecovery of moisture from standard.14. Precision14.1 The relative standard deviation for moisture in aconcentration range of 100 g/g is approximately 2 % butincreases to 10 % at the 20 g/g level.NITROGEN BY THE KJELDAHL METHOD15. Scope15.1 This test method covers the determination of nitridenitrogen
44、in uranium dioxide in the range from 10 to 250 g.16. Summary of Test Method16.1 The sample is decomposed with acid, the resultingsolution is made strongly alkaline with sodium hydroxidesolution, and the nitrogen is separated as ammonia by steamdistillation. The distillate is collected in boric acid
45、solution andthe ammonia present is titrated with 0.01 N standard acid usinga mixed indicator.NOTE 2Although a simple acid digestion is usually adequate fordissolution of uranium samples, some uranium nitrides do not yield tosuch treatment. The use of potassium dichromate in phosphoric acid (1)10has
46、proved to be successful with nitrides that are difficult to decompose.Therefore, this medium has been recommended although, in most cases, amixture of phosphoric and sulfuric acids would be adequate.17. Interferences17.1 There should be no interferences in nuclear-gradeuranium dioxide.8A CEC Solids
47、Moisture Analyzer, of Type 26-321A-MA is available fromDuPont Instruments Inc., S. ShamrockAve., Monrovia, CA91016. If you are awareof alternative suppliers, please provide this information to ASTM InternationalHeadquarters. Your comments will receive careful consideration at a meeting of therespons
48、ible technical committee,1which you may attend.9A Cahn Electrobalance, or equivalent, available from Cahn Division, VentrumInstrument Corp., Paramount, CA has been found satisfactory. If you are aware ofalternative suppliers, please provide this information to ASTM InternationalHeadquarters. Your co
49、mments will receive careful consideration at a meeting of theresponsible technical committee,1which you may attend.10The boldface numbers in parentheses refer to the list of references at the endof these methods.C696 11318. Apparatus18.1 Nitrogen Distillation Apparatus, micro.1118.2 Heater, 750-W electric, full-control.18.3 Burner, bunsen-type.18.4 Buret, micro, class A, 5- or 10-mL capacity, graduatedin 0.02-mL divisions.19. Reagents19.1 Ammonia-Free WaterPrepare by distillation or froman ion-exchange column.19.2 Boric Acid-Indicator SolutionDissolve 20
