1、Designation: C 1411 01Standard 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:C 698 Standard Test Method for Chemical, Mass Spectro-metric, and Spectrochemical Analysis of Nuclear-GradeMixed Oxides (U, Pu)O2), Sections 141-149.2C 833 Standard Spe
6、cification for Sintered (Uranium, Pluto-nium) Dioxide Pellets.2C 1008 Standard Specification for Sintered (Uranium, Plu-tonium) Dioxide Pellets - Fast Reactor Fuel.2C 1168 Standard Practice for Preparation and Dissolution ofPlutonium Materials for Analysis.2E 267 Standard Test Method for Uranium and
7、 PlutoniumConcentrations and Isotopic Abundances.33. Summary of Practice3.1 Solid samples are dissolved according 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
8、analy-sis using Method C 698, see Sec. 144 through 145 and 147.4through 149 or its replacement. Appropriate aliquants are takento provide up to 1 mg of plutonium on the ion exchangecolumn to be separated from 10 mg or less of uranium. Valenceadjustment is obtained by using one of two procedures asde
9、scribed in 3.1.1 and 3.1.2 or by an alternative methoddemonstrated by the user to perform the equivalent reduction/oxidation procedure.43.1.1 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
10、. Ferrous sulfate isadded to reduce all plutonium (VI) to plutonium (III), then 16M HNO3is added to oxidize plutonium (III) to plutonium (IV),and to adjust the final acid concentration to 8MHNO3.3.1.2 A hydrogen peroxide reduction may be used forrelatively pure samples which do not contain excessive
11、amounts of oxidizing impurities. The aliquant is dissolved in 8M HNO3. Hydrogen peroxide is added to the aliquant prior tofuming to reduce 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,
12、63.2 After valence adjustment, the resulting solution ispassed through an anion exchange column in the nitrate formwhich retains the plutonium; uranium and americium are notabsorbed. The adsorbed plutonium is washed with additional 8M nitric acid (HNO3) to remove impurities and then strippedfrom the
13、 column with 0.36 M hydrochloric acid (HCl) and 0.01M hydrofluoric acid (HF). The effluent containing the uraniumand 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 uranium iswashed with a
14、dditional concentrated HCl to remove theimpurities and then stripped from the column with 0.1 M HCl.4. Significance and Use4.1 Uranium and plutonium are used in nuclear reactor fueland must be analyzed to insure that they meet certain criteriafor isotopic composition as described in Specification C
15、8331This practice is under 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. 10, 2001. Published March 2001. Originallypublished as C 141199. Last previous edition C 141199.2Annual Book
16、of ASTM Standards, Vol 12.01.3Annual Book of ASTM Standards, Vol 12.02.4Reduction of all higher plutonium oxidation states to plutonium (III) by theaddition of hydroxylamine or NH2CLO4, followed by oxidation to plutonium (IV)by sodium nitrite and subsequent boiling to eliminate the nitrous fumes has
17、 beenfound to be acceptable. This method avoids the addition of Fe, which could interferewith electrodeposition of mass spectrometric samples.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, 100
18、 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.and 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 masss
19、pectrometry.4.2 In those facilities where perchloric acid use is tolerated,the ion exchange separation procedure in Test Method E 267may be used prior to isotopic abundance determination. Also,in those facilities where perchloric acid use is tolerated andwhen uranium and plutonium concentrations are
20、 to be deter-mined as well as isotopic abundances using the thermalionization mass spectrometer, the ion exchange separationprocedure in Test Method E 267 may be used.5. Interferences5.1 The separated heavy element fractions placed on massspectrometric filaments must be very pure. The quantityrequir
21、ed depends upon the sensitivity of the instrument detec-tion system. Chemical purity of the sample becomes moreimportant as the sample size decreases, because the ionemission of the sample is repressed by impurities.5.2 Organics from ion exchange resin degradation products,if present, could affect t
22、he response of the mass spectrometerduring the plutonium and uranium isotopic abundance mea-surements. Evaporation of the samples with concentrated nitricacid after the ion exchange separation has been found todestroy any resin degradation products.5.3 The use of hydrogen peroxide for valence adjust
23、ment,when possible, avoids the addition of iron, an element which isnot cleanly removed from uranium by HCl ion exchange.5.4 Elemental impurities, especially alkali elements, tend toproduce unstable ion emission and alter observed ratios in anunpredictable manner.5.5 Isobaric impurities or contamina
24、nts will 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-238.5.6 Extreme care must be taken to avoid contamination ofthe sample by environmental uranium. The level of uraniumcontamin
25、ation should 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.6. Apparatus6.1 Ion Exchange ColumnsDisposable, 0.9 cm id 3 3cmwith a 15 mL reservoir7.6.2 Beakers or Alternate Acceptab
26、le Containerspretreated, 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.6.3 Infrared Heating Lamps8or Hot Plate with adjustablelow
27、 and high heat settings.6.4 Transfer PipetsDisposable.7. Reagents7.1 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 Society9where suchspecificat
28、ions are available. 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 a
29、s noted.7.2 WaterUnless otherwise indicated, references to watershall be understood to mean laboratory accepted demineralizedor deionized water.7.3 Nitric Acid (sp gr 1.42), 15.9 Mconcentrated nitricacid (HNO3).7.4 Nitric Acid, 8 M Add 500 mL of HNO3(sp gr 1.42) toabout 400 mL of water and dilute to
30、 1 L.7.5 Nitric Acid, 4 M Add 250 mL of HNO3(sp gr 1.42) toabout 700 mL of water and dilute to 1 L with water.7.6 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.7.7 Hydrochloric Acid (sp gr 1.19), 12.1 Mconcentratedhydrochloric acid (HCl).7.8 Hyd
31、rofluoric Acid (sp gr 1.18), 28.9 Mconcentratedhydrofluoric acid (HF).7.9 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.7.10 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
32、 water and dilute to 1 L with water.7.11 Anion exchange resin, 50-100 mesh, wet, chlorideform for uranium separation.107.12 Anion exchange resin, nitrate form, 50-100 mesh, wet,for plutonium separation.11The exchange capacity of the resinshould be between 0.6 and 0.7 milliequivalents/gram of dryresi
33、n for optimum separation.7.12.1 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 r
34、esin.7.13 Sulfuric Acid (sp gr 1.84), 18.0 Mconcentratedsulfuric acid (H2SO4).7.14 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.7.15 Hydrogen Peroxide
35、 (H2O2,30%), stabilized.7Available from Bodman Industries, Aston PA; catalogue number 3300-25; 70micron frits, catalogue number 3201-00 have been found to be acceptable.8Quartz Epiradiateur Lamps Model 534 RCL, 500 watts, 120 volts, controlled bya 0-140 V variable power supply (Variac), from Atlas E
36、lectric Supplies, P.O. Box1300, Hialeah, FL, 33011, have been found acceptable.9“Reagent Chemicals, American Chemical Society Specifications,” AmericanChemical Society, Washington, DC.10Dowexx1-X2 or Bio-RadxAG 1-X2, chloride form has been found to beacceptable.11Dowexx1-X2 or Bio-RadxAG 1-X2, nitra
37、te form has been found to beacceptable.C 141128. Procedure8.1 Plutonium Anion Exchange Separation:8.1.1 Sample Preparation:8.1.1.1 Dissolve solid samples according to Practice C 1168or other appropriate methods. Aliquants of the solution con-taining the approximate desired quantity of element are ta
38、ken;the desired quantity of element will depend upon whether ornot the solution is diluted prior to filament loading.(WarningNo initial aliquant should contain more that 10 mgof uranium to prevent inadequate rinsing of the ion exchangeresin by the volumes given, and hence, inadequate separationof ur
39、anium and plutonium.)8.1.1.2 An aliquant containing up to 1 mg of plutonium istransferred to a new, acid leached 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 massspectr
40、ometric isotopic abundance determination.8.1.1.3 Fume the aliquant just to dryness on a hot plate orunder an infrared heat lamp. If the sample contains halides, add8MHNO3and dry two more times. (WarningOverheatingmay cause polymerization of plutonium or difficulty in subse-quent dissolution.)For sam
41、ples free of transition elements, proceed with 8.1.2for ferrous sulfate reduction or with 8.1.3 for hydrogenperoxide reduction. For all other samples, proceed with 8.1.2.8.1.2 Ferrous Sulfate Valence Adjustment:8.1.2.1 Dissolve the residue from 8.1.1.3 in 8 mL of 3MHNO3.8.1.2.2 Add 1 drop of 0.1 M F
42、eSO4solution, prepared theday of the ion exchange, from a disposable pipet. Swirl to mixwell. This will reduce all plutonium in higher oxidation statesto plutonium (III).8.1.2.3 Add 5 mL of 16 M HNO3. Swirl to mix well. Thiswill oxidize plutonium (III) to plutonium (IV) and adjust thesolution concen
43、tration to 8MHNO3.8.1.2.4 Proceed to 8.1.4.8.1.3 Hydrogen Peroxide Valence Adjustment:8.1.3.1 Dissolve the residue from 8.1.1.3 in 5 mL of 8MHNO3.8.1.3.2 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 cover
44、ed with a watchglass. Gentle effervescence should occur; continue heatinguntil the effervescence has stopped. Reduction of all plutonium(VI) to plutonium (IV) is critical to a successful ion exchangeseparation.8.1.3.3 Cool solution to room temperature.8.1.4 Anion Exchange:8.1.4.1 Fill the ion exchan
45、ge 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 t
46、he acid.8.1.4.2 Place a new, acid leached, labeled container underthe prepared ion exchange column to collect the uraniumfraction, and then transfer the sample from 8.1.2.4 or 8.1.3.3 tothe column. Rinse the sample beaker with at least 3 mL of 8MHNO3and transfer to the column; repeat rinse.8.1.4.3 A
47、dd enough 8MHNO3to the column to collect 10to 15 mL of eluate in the uranium fraction container, and set theeluate aside for uranium recovery in 8.2.8.1.4.4 Place a beaker to collect waste under the column.Wash the ion exchange column with successive 5 mL portionsof 8MHNO3until 30 mL have been used.
48、 Collect the washingsin the waste beaker and discard them to appropriate wastecontainers. Plutonium (IV) is adsorbed by the resin.8.1.4.5 When the last portion of 8MHNO3wash solutiondrains to the top of the resin bed, place a new, acid leached,labeled beaker under the column to collect the plutonium
49、fraction. Add 5 mL of the HCl/HF stripping solution to thecolumn slowly, using a transfer pipet, and collect the plutoniumfraction. Discard the column and resin to waste. (WarningIflarge amounts of uranium are present, 10 000 parts ofuranium to 1 part of plutonium, 8.1.1.3-8.1.4.5 may need to berepeated for complete purification of the plutonium.)8.1.4.6 Place the container of plutonium on a hot plate orunder an infrared heat lamp, and evaporate the solution todryness. (WarningOverheating may cause polymerizationof plutonium or difficulty in subsequent dissolu
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