1、Designation: C 809 94 (Reapproved 2007)Standard Test Methods forChemical, Mass Spectrometric, and SpectrochemicalAnalysis of Nuclear-Grade Aluminum Oxide and AluminumOxide-Boron Carbide Composite Pellets1This standard is issued under the fixed designation C 809; the number immediately following the
2、designation indicates 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 These test methods cover
3、procedures for the chemical,mass spectrometric, and spectrochemical analysis of nuclear-grade aluminum oxide and aluminum oxide-boron carbidecomposite pellets to determine compliance with specifications.1.2 The analytical procedures appear in the following order:SectionsBoron by Titrimetry 7 to 13Se
4、paration of Boron for Mass Spectrometry 14 to 19Isotopic Composition by Mass Spectrometry 20 to 23Separation of Halides by Pyrohydrolysis 24 to 27Fluoride by Ion-Selective Electrode 28 to 30Chloride, Bromide, and Iodide by Amperometric Microtitrimetry 31 to 33Trace Elements by Emission Spectroscopy
5、34 to 461.3 The values stated in SI units are to be regarded as thestandard.1.4 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 establish appro-priate safety and health practices and determi
6、ne the applica-bility of regulatory limitations prior to use. (For specificprecautionary statements, see Section 5.)2. Referenced Documents2.1 ASTM Standards:2C 784 Specification for Nuclear-Grade Aluminum Oxide-Boron Carbide Composite PelletsC 785 Specification for Nuclear-Grade Aluminum OxidePelle
7、ts3C 791 Test Methods for Chemical, Mass Spectrometric, andSpectrochemical Analysis of Nuclear-Grade Boron Car-bideC 799 Test Methods for Chemical, Mass Spectrometric,Spectrochemical, Nuclear, and Radiochemical Analysis ofNuclear-Grade Uranyl Nitrate SolutionsD 1193 Specification for Reagent WaterE1
8、15 Practice for Photographic Processing in OpticalEmission Spectrographic Analysis3E116 Practice for Photographic Photometry in Spectro-chemical Analysis33. Significance and Use3.1 Aluminum oxide pellets are used in a reactor core asfiller or spacers within fuel, burnable poison, or control rods. In
9、order to be suitable for this purpose, the material must meetcertain criteria for impurity content. These test methods aredesigned to show whether or not a given material meets thespecifications for these items as described in SpecificationC 785.3.1.1 Impurity content is determined to ensure that th
10、emaximum concentration limit of certain impurity elements isnot exceeded.3.2 Aluminum oxide-boron carbide composite pellets areused in a reactor core as a component in neutron absorber rods.In order to be suitable for this purpose, the material must meetcertain criteria for boron content, isotopic c
11、omposition, andimpurity content as described in Specification C 784.3.2.1 The material is assayed for boron to determinewhether the boron content is as specified by the purchaser.3.2.2 Determination of the isotopic content of the boron ismade to establish whether the10B concentration is in compli-an
12、ce with the purchasers specifications.3.2.3 Impurity content is determined to ensure that themaximum concentration limit of certain impurity elements isnot exceeded.1These test methods are under the jurisdiction of ASTM Committee C26 onNuclear Fuel Cycle and are the direct responsibility of Subcommi
13、ttee C26.03 onNeutron Absorber Materials Specifications.Current edition approved July 1, 2007. Published August 2007. Originallyapproved in 1980. Last previous edition approved in 2000 as C 809 94 (2000).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Se
14、rvice at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4. Reagents4.1 Purity of Reagen
15、tsReagent 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 available.4Other grades may beused, provided it
16、 is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.4.2 Purity of Water Unless otherwise indicated, referenceto water shall be understood to mean reagent water conformingto Specification D 1193, Type III.5. Safety
17、Precautions5.1 Many laboratories have established safety regulationsgoverning the use of hazardous chemicals and equipment. Theusers of these test methods should be familiar with such safetypractices.6. Sampling6.1 Criteria for sampling aluminum oxide pellets are givenin Specification C 785.6.2 Crit
18、eria for sampling aluminum oxide-boron carbidecomposite pellets are given in Specification C 784.BORON BY TITRIMETRY7. Scope7.1 This test method covers the determination of boron inaluminum oxide-boron carbide composites. As an alternative,the procedure for total boron by titrimetry detailed in Test
19、Methods C 791 may be used.8. Summary of Test Method8.1 The sample is crushed, passed through a 100-meshscreen, weighed in a glass boat, and introduced into a heavy-wall glass tube. Nitric acid is added to the tube and the contentsmixed using a vortex mixer. The tube is sealed, placed into asafety co
20、ntainer, heated for 6 h, cooled to room temperature,opened, and the contents washed into a beaker.5The solution isadjusted to pH 9.0 and filtered, then adjusted to pH 3.5 andboiled to remove CO2. Substantially, a pure boric acid isobtained which can be titrated in the presence of mannitol witha stan
21、dard solution of sodium hydroxide.6,79. Apparatus9.1 Analytical Balance, capable of weighing to 6 0.1 mg.9.2 Mortar, diamond (Plattner) (or equivalent).9.3 Sieve, No. 100 (150-m) U.S. Standard Sieve Series,76-mm diameter, brass or stainless steel.9.4 Glass Boats, borosilicate, 4-mm wide, 3-mm deep,4
22、0-mm long.9.5 Glass Tubing, heavy-wall borosilicate, 5-mm insidediameter by 250-mm long, sealed at one end.9.6 Mixer, vortex type.9.7 Glass Blowers Torch.9.8 Iron Pipe, 12.7 by 254-mm long with threaded end caps.9.9 Muffle Furnace, capable of operation at 300C. Theheated area must be of sufficient s
23、ize to hold the capped ironpipe.9.10 pH Meter, with pH electrodes and magnetic stirrer.9.11 Steam Bath.9.12 Hot Plate.9.13 Filter Paper, 11 cm, ashless slow filtering for fineprecipitates.9.14 Buret, Class A, 25-mL.10. Reagents10.1 Boric Acid, NIST SRM 951 or its replacement.10.2 Hydrochloric Acid (
24、HCl),1N.10.3 Hydrochloric Acid (HCl), 0.1 N.10.4 Mannitol.10.5 Nitric Acid (sp gr 1.42)Concentrated Nitric Acid(HNO3).10.6 Sodium Hydroxide (NaOH) Solution,1N, carbonate-free.10.7 Sodium Hydroxide (NaOH) Solution, 0.1 N, carbonate-free.10.8 Sodium Hydroxide (NaOH) Solution, 0.025 N,carbonate-free, s
25、tandardized against NIST SRM 951.11. Procedure11.1 Crush the aluminum oxide/boron carbide compositepellet using a diamond mortar until all the sample is passedthrough a No. 100 (150-m) screen.11.2 Weigh a 250-mg sample into a glass boat.11.3 Introduce the boat and sample into a heavy-wall glasstube,
26、 being very careful to prevent any of the sample fromadhering to the wall of the tube near the open end.11.4 Introduce 0.5 mL of concentrated HNO3into the glasstube.11.5 Mix the sample and acid using the vortex mixer.11.6 Flame the glass tube to remove the moisture from thewalls.11.7 Seal the glass
27、tube. There are two methods available:11.7.1 Sealing the glass tube may be accomplished byconstriction, then drawing off a short piece of the tube, thenworking down the sealed end.11.7.2 A seal can be made by allowing the open end of thetube to flow together by heating and revolving the tube slowly.
28、While the tube is red with heat, the tube is warmed enough toblow out the seal to a rounded shape.4Reagent Chemicals, American Chemical Society Specifications , AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar
29、 Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmaceutical Convention, Inc. (USPC), Rockville,MD.5Wichers, E., Schlecht, W. G., and Gordon, C. L., “Preparing Refractory Oxides,Silicates, and Ceramic Materials forAn
30、alysis by Heating withAcids in SealedTubesat Elevated Temperatures,” Journal of Research of the National Bureau ofStandards, Vol 33, 1944, p. 451.6Lerner, M. W., The Analysis of Elemental Boron, New Brunswick Laboratory,U. S. Atomic Energy Commission, TID-25190, November 1970.7Rodden, C. J., Analysi
31、s of Essential Nuclear Reactor Materials, U.S. AtomicEnergy Commission, Washington, DC, Government Printing Office, 1964.C 809 94 (2007)211.8 Place the glass tube into a safety container whichconsists of a 12.7-mm inside diameter black iron pipe withscrew caps on each end. The caps can be tightened
32、with fingertip control.11.9 Insert the assembly into a 300C muffle furnace withthe top end of the assembly elevated and heat for 6 h.11.10 Remove the assembly from the muffle furnace andplace into a tray, keeping the same end of the assemblyelevated.11.11 Allow the assembly to cool to room temperatu
33、re.11.12 Withdraw the glass tube from the safety container andfile a notch about 13 mm from one end of the tube.NOTE 1Contents of the tube may be under pressure.11.13 Heat a glass rod to red heat, then place the rod on thenotch. This action should crack the glass tube; however, a lighttap may be nee
34、ded to complete the break.11.14 Wash the contents from the glass tube into a 250-mLbeaker; however, if the aluminum oxide is stuck to the walls ofthe tube, shake on a vortex mixer.NOTE 2The matrix Al2O3does not completely dissolve, but all of theboron is in solution.11.15 Precipitate the iron and th
35、e aluminum by using 1 Nsodium hydroxide solution to adjust the pH to 9.0.11.16 Place the beaker on a steam bath and digest for 1 h.11.17 Filter the sample through the filter paper (9.13) andwash the precipitate with several portions of hot deionizedwater.11.18 Adjust the pH between 3.5 and 4.0 using
36、 1 N HCl.11.19 Cover the solution with a flat watch glass, then placethe beaker on a hot plate and boil for about 5 min to removecarbon dioxide.11.20 Remove the sample from the hot plate and cool toroom temperature in a water bath.11.21 Adjust the pH of the sample to 5.6 to 5.7 using 0.1 NNaOH solut
37、ion and 0.1 N HCl. Add 1 to3gofmannitol.11.22 Titrate the sample to pH 8.0 using a 0.025 N NaOHsolution.11.23 Determine a blank by performing 11.3-11.22 withoutthe sample.12. Calculation12.1 Calculate the percent boron in the sample as follows:B,%5V B!N!A!100!W(1)where:V = millilitres of NaOH soluti
38、on used in titration of thesample,B = millilitres of NaOH solution used in titration of theblank,N = normality of the NaOH solution,A = atomic weight of boron computed for the samplebased upon the measured isotopic composition, andW = milligrams of sample weight.13. Precision13.1 The limit of error
39、at the 95 % confidence level for asingle determination is 6 0.10 % absolute.SEPARATION OF BORON FOR MASSSPECTROMETRY14. Scope14.1 This test method covers the separation of boron fromaluminum and other impurities. The isotopic composition ofthe separated boron is measured using another test methodfou
40、nd herein.15. Summary of Test Method15.1 Boron is put into solution using a sealed-tube dissolu-tion method. It is separated from aluminum and other impuri-ties by solvent extraction and ion exchange.16. Interferences16.1 There are no known interferences not eliminated bythis separation test method.
41、17. Apparatus17.1 Separatory Funnel, 60-mL with TFE-fluorocarbonstopcock.17.2 Mixer, vortex type.17.3 Filter Paper, ashless, slow filtering for fine precipi-tates.17.4 Ion Exchange Column, borosilicate glass, 5-mm insidediameter, 100-mm long with a TFE-fluorocarbon stopcock.17.5 Beaker, 50-mL, quart
42、z or TFE-fluorocarbon.18. Reagents18.1 Cation Exchange Resin,880 to 100 mesh. Prepare theresin by treatment with 3 N HCl followed by water wash untilthe effluent is neutral to pH paper.18.2 Chloroform (CHCl3).18.3 2-Ethyl-1,3Hexanediol Solution, 5 volume % in chlo-roform.18.4 Nitric Acid (HNO3), 2 M
43、.18.5 Sodium carbonate (Na2CO3), powder.18.6 Sodium Hydroxide (NaOH) Solution, 0.1 N,carbonate-free. Store in a plastic bottle.19. Procedure19.1 Prepare an aliquot of sample by following 11.1-11.13.19.2 Pipet 4 mL of water into the glass tube and mix usinga vortex mixer.19.3 Filter the solution thro
44、ugh filter paper (15.3). Catch thefiltrate in a 60-mL separatory funnel.19.4 Wash the paper with 15-mL of 2 M HNO3. Catch thewash in the separatory funnel.19.5 Add 10 mL of 5 % 2-ethyl-1,3 hexanediol solution tothe separatory funnel and shake for 2 min.19.6 Drain the organic (lower) layer into a cle
45、an 100-mLbeaker.19.7 Repeat 19.5 and 19.6.19.8 Transfer the 2-ethyl-1,3 hexanediol solution to a clean60-mL separatory funnel.8Dowex 50 3 8 (or equivalent).C 809 94 (2007)319.9 Extract the boron by shaking for 2-min with a NaOHsolution containing the amount of sodium calculated to give aB/Na ratio o
46、f two and a volume sufficient to give 1 mg B/mL.19.10 Discard the organic phase.19.11 Wash the aqueous phase with two 5-mL portions ofCHCl3. Discard the organic wash.19.12 Transfer the aqueous phase containing the boron to a50-mL quartz or TFE-fluorocarbon beaker.19.13 Evaporate the solution to a vo
47、lume of about 1 mL.19.14 Add 0.5 mL of ion exchange resin to the beaker andswirl.NOTE 3Addition of the resin to the beaker prevents formation of CO2bubbles on the resin column in the subsequent step.19.15 Transfer the slurry to a prepared resin column con-taining a 10-mm depth of resin.19.16 Elute t
48、he boron with an amount of water calculated toyield a solution containing 1 mg B/mL.19.17 Add solid Na2CO3to give a Na/B ratio of 0.9 to 1.0.Transfer the solution to a plastic bottle.ISOTOPIC COMPOSITION BY MASSSPECTROMETRY20. Scope20.1 This test method covers the determination of theisotopic compos
49、ition of boron in nuclear-grade aluminumoxide/boron carbide composite pellets containing natural tohighly enriched boron.21. Summary of Test Method21.1 Boron isotopic ratios are measured in aluminum oxide/boron carbide composites by thermal ionization mass spec-trometry following chemical separation of boron. The loadedfilament is transferred to the mass spectrometer where boronisotopic ratios are measured using the Na2BO2+ion. Whenmixing the boron and sodium carbonate, a Na to B ratio of 1:1is maintained, which gives a stable ion emission within a fewminutes after
