1、Designation: C 1411 08Standard Practice forThe Ion Exchange Separation of Uranium and PlutoniumPrior to Isotopic Analysis1This standard is issued under the fixed designation C 1411; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, t
2、he 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 practice is for the ion exchange separation ofuranium and plutonium from each other and from otherimp
3、urities for subsequent isotopic analysis by thermal ioniza-tion mass spectrometry. Plutonium238 and uranium238, andplutonium241 and americium241, will appear as the samemass peak and must be chemically separated prior to analysis.Only high purity solutions can be analyzed reliably usingthermal ioniz
4、ation mass spectrometry.1.2 This standard may involve hazardous material, opera-tions, and equipment. This standard does not purport toaddress all of the safety concerns, if any, associated with itsuse. It is the responsibility of the user of this standard toconsult and establish appropriate safety
5、and health practicesand determine the applicability of regulatory limitations priorto use.2. Referenced Documents2.1 ASTM Standards:2C 698 Test Methods for Chemical, Mass Spectrometric, andSpectrochemicalAnalysis of Nuclear-Grade Mixed Oxides(U, Pu)O2)C 833 Specification for Sintered (Uranium-Pluton
6、ium) Di-oxide PelletsC 859 Terminology Relating to Nuclear Materials3C 1008 Specification for Sintered (Uranium-Plutonium) Di-oxide PelletsFast Reactor FuelC 1168 Practice for Preparation and Dissolution of Pluto-nium Materials for AnalysisC 1347 Practice for Preparation and Dissolution of UraniumMa
7、terials for AnalysisC 1625 Test Method for Uranium and Plutonium Concen-trations and Isotopic Abundances by Thermal IonizationMass Spectrometry3. Terminology3.1 Definitions: For definitions of terms used in this stan-dard, refer to C 859.4. Summary of Practice4.1 Solid samples are dissolved accordin
8、g to PracticeC 1168 or other appropriate methods. The resulting solution isprocessed by this practice to prepare separate solutions ofplutonium and uranium for mass spectrometric isotopic analy-sis using Method C 698, sections 112.4 through 114 or methodC 1625. Appropriate aliquants are taken to pro
9、vide up to 1 mgof plutonium on the ion exchange column to be separated from10 mg or less of uranium. Valence adjustment is obtained byusing one of two procedures as described in 4.1.1 and 4.1.2 orby an alternative method demonstrated by the user to performthe equivalent reduction/oxidation procedure
10、.44.1.1 For any sample type, especially those containing largeamounts of impurities, ferrous sulfate may be used for reduc-tion. The aliquant is dissolved in 3 M HNO3. Ferrous sulfate isadded to reduce all plutonium (VI) to plutonium (III), then 16M HNO3is added to oxidize plutonium (III) to plutoni
11、um (IV),and to adjust the final acid concentration to 8MHNO3.4.1.2 A hydrogen peroxide reduction may be used forrelatively pure samples which do not contain excessiveamounts of oxidizing impurities. The aliquant is dissolved in 8M HNO3. Hydrogen peroxide is added to the aliquant prior tofuming to re
12、duce plutonium (VI) to the lower oxidation states.The solution is warmed on a hot plate to destroy excesshydrogen peroxide and stabilize plutonium (IV) in solution.5,64.2 After valence adjustment, the resulting solution ispassed through an anion exchange column in the nitrate formwhich retains the p
13、lutonium; uranium and americium are notabsorbed. The adsorbed plutonium is washed with additional 8M nitric acid (HNO3) to remove impurities and then strippedfrom the column with 0.36 M hydrochloric acid (HCl) and 0.01M hydrofluoric acid (HF). The effluent containing the uranium1This practice is und
14、er the jurisdiction of ASTM Committee C26 on NuclearFuel Cycle and is the direct responsibility of Subcommittee C26.05 on Methods ofTest.Current edition approved Jan. 1, 2008. Published February 2008. Originallyapproved in 1990. Last previous edition approved in 2001 as C 1411 01.2For referenced AST
15、M 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.3Withdrawn.4Reduction of all higher plutonium oxidation states to plutonium (III
16、) by theaddition of hydroxylamine or NH2CLO4, followed by oxidation to plutonium (IV)by sodium nitrite and subsequent boiling to eliminate the nitrous fumes has beenfound to be acceptable. This method avoids the addition of Fe, which could interferewith electrodeposition of mass spectrometric sample
17、s.5I.V. Kressin and G.R. Waterbury, Anal. Chem. 34(12) , 1598 (1962).6C.E. Pietri, B.P. Freeman, and J.R. Weiss, DOE/NBL-298 , September 1981.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Copyright by ASTM Intl (all rights reserved
18、); Thu Feb 19 02:07:54 EST 2009Downloaded/printed byGuo Dehua (CNIS) pursuant to License Agreement. No further reproductions authorized.and americium is converted to a HCl medium, and this solutionis passed through an anion exchange column in the chlorideform which retains the uranium. The adsorbed
19、uranium iswashed with additional concentrated HCl to remove theimpurities and then stripped from the column with 0.1 M HCl.5. Significance and Use5.1 Uranium and plutonium are used in nuclear reactor fueland must be analyzed to insure that they meet certain criteriafor isotopic composition as descri
20、bed in Specification C 833and Specification C 1008. This standard practice is used tochemically separate the same mass peak interferences fromuranium and plutonium and from other impurities prior toisotopic abundance determination by thermal ionization massspectrometry.5.2 In those facilities where
21、perchloric acid use is tolerated,the separation in Test Method C 698 may be used prior toisotopic abundance determination. Uranium and plutoniumconcentrations as well as isotopic abundances using thermalionization mass spectrometry can be determined using thisseparation and following Test Method C 1
22、625.6. Interferences6.1 The separated heavy element fractions placed on massspectrometric filaments must be very pure. The quantityrequired depends upon the sensitivity of the instrument detec-tion system. Chemical purity of the sample becomes moreimportant as the sample size decreases, because the
23、ionemission of the sample is repressed by impurities.6.2 Organics from ion exchange resin degradation products,if present, could affect the response of the mass spectrometerduring the plutonium and uranium isotopic abundance mea-surements. Evaporation of the samples with concentrated nitricacid afte
24、r the ion exchange separation has been found todestroy any resin degradation products. Organics from extrac-tion resins may not be destroyed by this process, and willrequire a perchloric acid treatment, heating in a furnace at500C, or both.6.3 The use of hydrogen peroxide for valence adjustment,when
25、 possible, avoids the addition of iron, an element which isnot cleanly removed from uranium by HCl ion exchange.6.4 Elemental impurities, especially alkali elements, tend toproduce unstable ion emission and alter observed ratios in anunpredictable manner.6.5 Isobaric impurities or contaminants will
26、alter the ob-served isotopic ratios; most notable of these for plutonium areamericium-241 and uranium-238; the most notable isobaricimpurity for uranium is plutonium-238.6.6 Extreme care must be taken to avoid contamination ofthe sample by environmental uranium. The level of uraniumcontamination sho
27、uld be measured by analyzing an aliquant of8MHNO3reagent as a blank taken through the same chemicalprocessing as the sample and computing the amount ofuranium it contains.7. Apparatus7.1 Ion Exchange ColumnsDisposable, 0.9 cm id 3 3cmwith a 15 mL reservoir.7.2 Beakers or Alternate Acceptable Contain
28、erspretreated, 20-30 mL, borosilicate glass. To avoid cross con-tamination, use only new borosilicate glass containers pre-treated by heating in 4 M HNO3to leach uranium, rinsed indeionized water, and air or oven dried prior to use.7.3 Infrared Heating Lamps or Hot Plate with adjustablelow and high
29、heat settings.7.4 Transfer PipetsDisposable.8. Reagents8.1 Reagent grade or better chemicals should be used.Unless otherwise indicated, it is intended that all reagentsconform to the specifications of the Committee on AnalyticalReagents of the American Chemical Society7where suchspecifications are a
30、vailable. Other grades of reagents may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of measurements made on the prepared materials.Store solutions in appropriate polyethylene or glass bottlesexcept as noted.8.
31、2 WaterUnless otherwise indicated, references to watershall be understood to mean laboratory accepted demineralizedor deionized water.8.3 Nitric Acid (sp gr 1.42), 16 Mconcentrated nitric acid(HNO3).8.4 Nitric Acid, 8 M Add 500 mL of HNO3(sp gr 1.42) toabout 400 mL of water and dilute to 1 L.8.5 Nit
32、ric Acid, 4 M Add 250 mL of HNO3(sp gr 1.42) toabout 700 mL of water and dilute to 1 L with water.8.6 Nitric Acid, 3 M Add 187 mL of HNO3(sp gr 1.42) toabout 750 mL of water and dilute to 1 L with water.8.7 Hydrochloric Acid (sp gr 1.19), 12 Mconcentratedhydrochloric acid (HCl).8.8 Hydrofluoric Acid
33、 (sp gr 1.18), 29 Mconcentratedhydrofluoric acid (HF).8.9 Hydrochloric Acid, 0.1 MAdd 8 mL of HCl (sp gr1.19) to about 900 mL of water and dilute to 1 L with water.8.10 Stripping solution (0.36 M HCl, 0.01 M HF)Add 30mL of HCl (sp gr 1.19) and 0.4 mL HF (sp gr 1.18) to about900 mL of water and dilut
34、e to 1 L with water.8.11 Anion exchange resin, 50-100 mesh, wet, chlorideform for uranium separation.8.12 Anion exchange resin, nitrate form, 50-100 mesh, wet,for plutonium separation. The exchange capacity of the resinshould be between 0.6 and 0.7 milliequivalents/gram of dryresin for optimum separ
35、ation.8.12.1 WarningThe dry and wet mesh size of the resinsdiffer; for the hydrochloride form of the resin, a 100-200 mesh,dry resin is purchased to provide 50-100 mesh, wet resin. The100-200 mesh dry hydrochloride resin may be used to preparethe 50-100 mesh, wet nitrate form of resin.7Reagent Chemi
36、cals, 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
37、 Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.C1411082Copyright by ASTM Intl (all rights reserved); Thu Feb 19 02:07:54 EST 2009Downloaded/printed byGuo Dehua (CNIS) pursuant to License Agreement. No further reproductions authorized.8.13 Sulfuric Acid (sp gr 1.84), 18 Mconcent
38、rated sulfuricacid (H2SO4).8.14 Ferrous Sulfate Solution (0.1 M)add 1.5 g of ferroussulfate heptahydrate (FeSO47H2O) to approximately 40 mLof water; add 0.3 mL (7 drops) concentrated sulfuric acid anddilute to 50 mL with water.8.15 Hydrogen Peroxide (H2O2,30%), stabilized.9. Precautions9.1 Strong ac
39、ids are used during this analysis. Safety glassesand gloves must be worn when handling these solutions.Extreme care should be exercised in using hydrofluoric acidand other hot concentrated acids.Acid solutions are evaporatedduring this analysis. These operations must be conducted in afume hood.9.2 H
40、ydrofluoric acid is a highly corrosive and toxic acidthat can severly burn skin, eyes, and mucous membranes.Hydrofluoric acid differs from other acids because the fluorideion readily penetrates the skin, causing destruction of deeptissue layers. Unlike other acids that are rapidly neutralized,hydrof
41、luoric acid reactions with tissue may continue for days ifleft untreated. Utilization of appropriate laboratory controlsand wearing adequate personal protective equipment to protectfrom skin and eye contact is essential.10. Procedure10.1 Plutonium Anion Exchange Separation:10.1.1 Sample Preparation:
42、10.1.1.1 Dissolve solid samples according to PracticeC 1168, C 1347, or other appropriate methods.Aliquants of thesolution containing the approximate desired quantity of ele-ment are taken; the desired quantity of element will dependupon whether or not the solution is diluted prior to filamentloadin
43、g. (WarningNo initial aliquant should contain morethat 10 mg of uranium to prevent inadequate rinsing of the ionexchange resin by the volumes given, and hence, inadequateseparation of uranium and plutonium.)10.1.1.2 An aliquant containing up to 1 mg of plutonium istransferred to a new, acid leached
44、20-30 mL container for ionexchange preparation.NOTE 1From this separation, a maximum of 200 ng of plutonium or2 g of uranium will be loaded on a filament for thermal ionization massspectrometric isotopic abundance determination.10.1.1.3 Fume the aliquant just to dryness on a hot plate orunder an inf
45、rared heat lamp. If the sample contains halides, add8MHNO3and dry two more times. (WarningOverheatingmay cause polymerization of plutonium or difficulty in subse-quent dissolution.)For samples free of transition elements, proceed with 10.1.2for ferrous sulfate reduction or with 10.1.3 for hydrogenpe
46、roxide reduction. For all other samples, proceed with 10.1.2.10.1.2 Ferrous Sulfate Valence Adjustment:10.1.2.1 Dissolve the residue from 10.1.1.3 in8mLof3MHNO3.10.1.2.2 Add 1 drop of 0.1 M FeSO4solution, prepared theday of the ion exchange, from a disposable pipet. Swirl to mixwell. This will reduc
47、e all plutonium in higher oxidation statesto plutonium (III).10.1.2.3 Add 5 mL of 16 M HNO3. Swirl to mix well. Thiswill oxidize plutonium (III) to plutonium (IV) and adjust thesolution concentration to 8MHNO3.10.1.2.4 Proceed to 10.1.4.10.1.3 Hydrogen Peroxide Valence Adjustment:10.1.3.1 Dissolve t
48、he residue from 10.1.1.3 in5mLof8MHNO3.10.1.3.2 Add 4 drops of 30 % H2O2from a disposable pipet.Place the beaker on a hot plate at low heat (80 C) for aminimum of 1.5 h while the beaker is covered with a watchglass. Gentle effervescence should occur; continue heatinguntil the effervescence has stopp
49、ed. Reduction of all plutonium(VI) to plutonium (IV) is critical to a successful ion exchangeseparation.10.1.3.3 Cool solution to room temperature.10.1.4 Anion Exchange:10.1.4.1 Fill the ion exchange column with a water slurry ofthe nitrate resin to a settled height of 1-2 cm. Pass 10 mL of 8M HNO3through the resin, and then add 5 mL of 8MHNO3and drain just before the sample is added. The column shouldbe prepared the same day as the ion exchange is done toprevent degradation of the resin in the acid.10.1.4.2 Place a new, acid leached, labeled container un