1、Designation: E 37 05Standard Test Methods forChemical Analysis of Pig Lead1This standard is issued under the fixed designation E 37; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the year of last revision. A number in parentheses
2、 indicates the year of last reapproval. A superscriptepsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 These test methods cover the chemical analysis of piglead having chemical compositions within the following limits:Element Concentration Range, %Antimony 0
3、.001 to 0.02Arsenic 0.0005 to 0.02Bismuth 0.002 to 0.2Copper 0.001 to 0.1Iron 0.0005 to 0.005Lead 99.5 to 99.99Silver 0.001 to 0.03Tin 0.001 to 0.02Zinc 0.001 to 0.0051.2 The test methods appear in the following order:SectionsAntimony by the Rhodamine-B Photometric Method 21-30Copper, Bismuth, Silve
4、r, and Zinc by the Atomic AbsorptionMethod10-201.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility
5、 of the user of this standard to consult andestablish appropriate safety and health practices and deter-mine the applicability of regulatory limitations prior to use.Specific precautionary statements are given in the individualtest methods.2. Referenced Documents2.1 ASTM Standards:2B29 Specification
6、 for Refined LeadE29 Practice for Using Significant Digits in Test Data toDetermine Conformance With SpecificationsE50 Practices for Apparatus, Reagents, and Safety Precau-tions for Chemical Analysis of Metals, Ores, and RelatedMaterialsE60 Practice for Analysis of Metals, Ores, and RelatedMaterials
7、 by Molecular Absorption SpectrometryE 135 Terminology Relating to Analytical Chemistry forMetals, Ores, and Related MaterialsE 173 Practice for Conducting Interlaboratory Studies ofMethods for Chemical Analysis of Metals3E 1601 Practice for Conducting an Interlaboratory Study toEvaluate the Perform
8、ance of an Analytical Method3. Terminology3.1 For definitions of terms used in this test method, refer toTerminology E 135.4. Significance and Use4.1 These test methods for the chemical analysis of metalsand alloys are primarily intended to test such materials forcompliance with compositional specif
9、ications. It is assumedthat all who use these methods will be trained analysts capableof performing common laboratory procedures skillfully andsafely. It is expected that work will be performed in a properlyequipped laboratory.5. Apparatus, Reagents, and Photometric Practice5.1 Apparatus and reagent
10、s required for each determinationare listed in separate sections of each test method. Theapparatus, standard solutions, and reagents conform to therequirements prescribed in Practices E50. Photometers shallconform to the requirements prescribed in Practice E60.6. Safety Hazards6.1 For precautions to
11、 be observed in the use of certainreagents in these test methods, refer to Practices E 50.7. Sampling7.1 For procedures for sampling the material, refer toSpecification B29.1These test methods are under the jurisdiction of ASTM Committee E01 onAnalytical Chemistry for Metals, Ores, and Related Mater
12、ials and are the directresponsibility of Subcommittee E01.05 on Cu, Pb, Zn, Cd, Sn, Be, TheirAlloys, andRelated Metals.Current edition approved Oct. 1, 2005. Published November 2005. Originallyapproved in 1942. Last previous edition approved in 2000 as E 37 00.2For referenced ASTM standards, visit t
13、he 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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA
14、19428-2959, United States.8. Rounding Calculated Values8.1 Calculated values shall be rounded to the desired num-ber of places as directed in Practice E29.9. Interlaboratory Studies9.1 These test methods have been evaluated in accordancewith Practice E 173, unless otherwise noted in the precisionsec
15、tion.COPPER, BISMUTH, SILVER, AND ZINC BY THEATOMIC ABSORPTION METHOD10. Scope10.1 This test method covers the determination of bismuthin concentrations from 0.002 to 0.2 %, copper from 0.001 to0.1 %, silver from 0.001 to 0.03 %, and zinc from 0.001 to0.005 %.11. Summary of Test Method11.1 The sampl
16、e is dissolved in a nitric-perchloric acidmixture, the solution is fumed, and hydrochloric acid is addedto precipitate lead chloride. The hydrochloric-perchloric acidsolution is aspirated into the air-acetylene flame of an atomicabsorption spectrophotometer. The absorption of the resonanceline energ
17、y from the spectrum of each element is measured andcompared with that of calibration solutions of the sameelement. The lines used were Cu 324.7, Bi 223.0, Ag 328.0,and Zn 213.8 nm12. Concentration Range12.1 The concentration range for each element must bedetermined experimentally because the optimum
18、 range willdepend upon the individual instrument. Determine the appro-priate concentration range of each element as follows:12.1.1 Prepare a dilute standard solution as directed inSection 16. Refer to 16.1 for suggested initial concentrations.12.1.2 Prepare the instrument for use as directed in 18.1
19、.Measure the instrument response while aspirating water, thecalibration solution with the lowest concentration, and the twowith the highest concentrations. Determine the minimumresponse and the curve linearity as directed in 14.1.1 and14.1.2, respectively.12.1.3 If the instrument meets or surpasses
20、the minimumresponse and curve linearity criteria, the initial concentrationrange may be considered suitable for use. In this case proceedas directed in 12.1.5.12.1.4 If the minimum response is not achieved, prepareanother dilute standard solution to provide a higher concentra-tion range, and repeat
21、12.1.2 and 12.1.3. If the calibration curvedoes not meet the linearity criterion, prepare another dilutestandard solution to provide a lower concentration range, andrepeat 12.1.2 and 12.1.3. If a concentration range cannot befound for which both criteria can be met, do not use thismethod until the p
22、erformance of the apparatus has beenimproved.12.1.5 Perform the stability test as directed in 14.1.3.Ifeither of the minimum stability requirements is not met, do notuse this method until the repeatability of the readings has beensuitably improved.13. Interferences13.1 Elements ordinarily present do
23、 not interfere if theirconcentrations are under the maximum limits shown in 1.1.14. Apparatus14.1 Atomic Absorption SpectrophotometerUse hollow-cathode lamps, operated in accordance with manufacturersrecommendations as sources for the following lines: Cu 324.7,Bi 223.0, Ag 328.0, and Zn 213.8 nm. As
24、pirate the solutionsinto an air-acetylene flame of a premix burner. Determine thatthe atomic absorption spectrophotometer is satisfactory for usein this method by proceeding as directed in 14.1.1-14.1.3.NOTE 1Optimum settings for the operating parameters of the atomicabsorption spectrophotometer var
25、y from instrument to instrument.14.1.1 Minimum Response Calculate the difference be-tween the readings of the two highest of five equally spaced(16.2) calibration solutions. This difference must be at least 40scale units.NOTE 2The scale unit is defined as the smallest numerical intervalthat is estim
26、ated in taking each reading on the instrument. If the scale isnon-linear, the largest unit defined in this manner is used.14.1.2 Curve Linearity Calculate the difference betweenthe scale readings obtained with water and the lowest of thefive equally spaced calibration solutions. If necessary, conver
27、tthis difference and the difference calculated in 14.1.1 toabsorbance. Divide the difference for the highest interval bythat for the lowest interval. If this ratio is not 0.70 or greater,proceed as directed in 12.1.4.14.1.3 Minimum StabilityIf the variability of the readingsof the highest calibratio
28、n solution and of water is not less than1.8 % and 1.4 %, respectively, as calculated below, proceed asdirected in 12.1.5.VC5100C(C C!2n 1(1)Vo5100C(O O!2n 1(2)where:VC= percent variability of the highest calibrationreadings,C= average absorbance value for the highestcalibration solution,( (CX)2= sum
29、 of the squares of the n differencesbetween the absorbance readings of the high-est calibration solution and their average,VO= percent variability of the readings on waterrelative to C,O= average absorbance value of water,(OO)2= sum of the squares of the n difference be-tween the absorbance readings
30、 of water andtheir average, andn = number of determinations, three or more.15. Reagents15.1 Bismuth, Standard Solution (1 mL = 1 mg Bi)Transfer1gofbismuth (purity: 99.9 % min) to a 400-mLbeaker and dissolve in 50 mL of HNO3(1 + 1), heating gentlyE37052if necessary. When dissolution is complete, cool
31、, transfer to a1-L volumetric flask, add 100 mL of HNO3(1 + 1), dilute tovolume, and mix. Store in a polyethylene bottle.15.2 Copper, Standard Solution (1 mL = 1 mg Cu)Proceed as directed in 15.1, but substitute1gofcopper (purity:99.9 % min) for the bismuth.15.3 Silver, Standard Solution (1 mL = 1 m
32、g Ag)Proceedas directed in 15.1 but substitute1gofsilver (purity: 99.9 %min) for the bismuth.15.4 Zinc, Standard Solution (1 mL = 0.1 mg Zn)Proceedas directed in 15.1 but substitute 0.1 g of zinc (purity: 99.9 %min) for the bismuth.16. Calibration16.1 Dilute Standard SolutionUsing pipets, transfer t
33、o500-mL volumetric flasks the following volumes of eachstandard solution: bismuth, 20 mL; copper, 10 mL; silver, 5mL; and zinc, 10 mL. Dilute to volume and mix. Adjust theconcentration of a dilute standard solution if the proper rangeis not obtained when the 5, 10, 15, 20, and 25-mL portions aredilu
34、ted to 100 mL and tested.16.2 Calibration SolutionsPrepare five calibration solu-tions for each element to be determined. Using pipets, transfer5, 10, 15, 20, and 25-mL portions of the appropriate dilutestandard solution to 100-mL volumetric flasks. Add sufficientvolumes of HCl and HClO4to each flas
35、k to yield final acidconcentrations equal to that of the corresponding test solution,dilute to volume, and mix. Do not use solutions that have stoodmore than 24 h.17. Procedure17.1 Test Solution:17.1.1 Transfer a 10 g sample, weighed to the nearest 10mg, to a 300-mL Erlenmeyer flask (Note 3). Add 3
36、mL ofHNO3and 15 mL of HClO4, and heat until dissolution iscomplete. Evaporate to strong fumes of perchloric acid andcool.NOTE 3Due to the limited solubility of silver chloride, the silverconcentration in the sample solution should be less than 1 mg/100 mL. Ifthe expected silver concentration is high
37、er than 0.01 %, choose a sampleweight that limits the silver concentration to less than 1 mg/100 mL.17.1.2 Add 50 mL of water and, while swirling, heat toboiling. Add 25 mL of HCl. If less than a 10-g sample is used,add 20 mL HCl plus 0.5 mL for each gram of sample used.Heat again to boiling and coo
38、l to room temperature.17.1.3 Transfer the solution and precipitate to a 100-mLvolumetric flask, dilute to volume with water, and mix thor-oughly. Allow the precipitated lead chloride to settle. Use thesupernatant solution, or dilute an appropriate aliquot of thesupernatant solution to provide a conc
39、entration of the elementbeing measured which lies within the concentration rangedetermined in Section 12.17.2 Reagent Blank SolutionPrepare a reagent blank byadding 3 mL of HNO3and 15 mL of HClO4to a 300-mLErlenmeyer flask and proceed as directed in 17.1.18. Measurement18.1 Instrument AdjustmentOpti
40、mize the response of theinstrument as directed in 18.1.1-18.1.4.18.1.1 Set the instrument parameters approximately at thevalues obtained in 14.1, and light the burner.18.1.2 Adjust the instrument to the approximate wavelengthfor the element to be determined, permit the instrument toreach thermal equ
41、ilibrium, and complete the wavelength ad-justment to obtain maximum absorption while aspirating thehighest calibration solution.18.1.3 Optimize fuel, air, and burner adjustments whileaspirating the highest calibration solution.18.1.4 Aspirate water long enough to establish that theabsorbance reading
42、 is stable and then set the initial reading(approximately zero absorbance or 100 % transmittance).18.2 Photometry:18.2.1 Aspirate the test solution and note, but do not recordthe reading.NOTE 4Avoid transferring particles of precipitated lead chloride thatmay clog the aspirator during the measuremen
43、ts of the test solution.18.2.2 Aspirate water until the initial reading is againobtained. Aspirate the calibration solutions and test solution inorder of increasing instrument response, starting with thereagent blank. When a stable response is obtained for eachsolution, record the reading.18.2.3 Pro
44、ceed as directed in 18.2.2 at least twice more.19. Calculations19.1 Calculate the variability of the readings for water andthe highest calibration solution as directed in 14.1.3 to deter-mine whether they are less than 1.4 % and 1.8 %, respectively.If they are not, disregard the data, readjust the i
45、nstrument, andproceed again as directed in 18.2.19.2 If necessary, convert the average of the readings foreach calibration solution to absorbance. Calculate the netabsorbance of the test solution by subtracting the absorbance ofthe reagent blank solution.19.3 Prepare a calibration curve by plotting
46、the absorbancevalues for the calibration solutions against milligrams of theelements per millilitre.19.4 Convert the net absorbance value of the test solution tomilligrams of the element per millilitre by means of theappropriate calibration curve.19.5 Calculate the percentage of the element as follo
47、ws(Note 5):Element, % 5 A 3 B 3 0.977!/C 3 100 (3)where:A = milligrams of element per millilitre,B = final volume of test solution in millilitres, andC = milligrams of sample represented in final volume oftest solution.NOTE 5The factor 0.977 is used to compensate for the volume errorin the 100 mL of
48、 final test solution caused by the 13.1 g of lead chlorideprecipitate. If less than 10 g of sample is used, calculate and apply anappropriate factor.20. Precision and Bias20.1 PrecisionSeven laboratories cooperated in testingthis method, with one laboratory reporting a second pair ofvalues; the data
49、 are summarized in Table 1.E3705320.2 BiasThe accuracy of this method could not beevaluated because adequate certified reference materials wereunavailable at the time of testing. The user is cautioned toverify by the use of certified reference materials, if available,that the accuracy of this method is adequate for the contem-plated use.20.3 Practice E 173 has been replaced by Practice E 1601.The Reproducibility Index R2of Practice E 173 corresponds tothe Reproducibility Index R of Practice E 1601. Likewise theRepeatability Index R1of Prac
