1、Designation: D 521 02 (Reapproved 2007)Standard Test Methods forChemical Analysis of Zinc Dust (Metallic Zinc Powder)1This standard is issued under the fixed designation D 521; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the ye
2、ar 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 procedures for the chemicalanalysis of metallic zinc powder in the form commerciallykn
3、own as zinc dust for use as a pigment in paints.1.2 The analytical procedures appear in the following order:SectionsMoisture and Other Volatile Matter 7Coarse Particles 8Matter Soluble in Hexane 9 and 10Total Zinc 11 and 12Metallic Zinc 13 and 14Zinc Oxide 15Calcium 16 and 17Lead 18Iron 19Cadmium 20
4、Chlorine 21 and 22Sulfur 23 and 241.3 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 of the user
5、of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2B 214 Test Method for Sieve Analysis of Metal PowdersD 185 Test Methods for Coarse Particles in Pigments,Pastes, a
6、nd PaintsD 280 Test Methods for Hygroscopic Moisture (and OtherMatter Volatile Under the Test Conditions) in PigmentsD 1193 Specification for Reagent WaterD 6580 Test Method for The Determination of MetallicZinc Content in Both Zinc Dust Pigment and in CuredFilms of Zinc-Rich CoatingsE40 Method for
7、Chemical Analysis of Slab Zinc (Spelter)3E68 Method for Polarographic Determination of Lead andCadmium in Zinc33. Significance and Use3.1 These test methods compile procedures which can beused to check the composition of purity of metallic zincpowder. This information is useful to both the formulato
8、r andusers.4. Treatment of Sample4.1 Store the laboratory sample in a tightly stoppered bottleto protect it from oxidation. Mix the whole sample thoroughlybefore taking portions for analysis.5. Purity of Reagents5.1 Purity of ReagentsUnless otherwise indicated, it isintended that all reagents shall
9、conform to the specifications ofthe Committee onAnalytical Reagents of theAmerican Chemi-cal Society, where such specifications are available.4Othergrades may be used, provided it is first ascertained that thereagent is of sufficiently high purity to permit its use withoutlessening the accuracy of t
10、he determination.5.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean reagent water conformingto Type II of Specification D 1193.6. Precision6.1 Precision statements have not been established.MOISTURE AND OTHER VOLATILE MATTER7. Procedure7.1 Determine moistur
11、e and other volatile matter in accor-dance with Method A of Test Methods D 280, except heat thesample for only 1 h.1These test methods are under the jurisdiction of ASTM Committee D01 onPaint and Related Coatings, Materials, and Applications and are the directresponsibility of Subcommittee D01.31 on
12、 Pigment Specifications.Current edition approved June 1, 2007. Published June 2007. Originallyapproved in 1939. Last previous edition approved in 2002 as D 521 02.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book
13、 of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn.4Reagent Chemicals, American Chemical Society Specifications , AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Soci
14、ety, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, Un
15、ited States.COARSE PARTICLES8. Procedure8.1 Determine the percent of coarse particles in the pigmentin accordance with Test Methods D 185 or B 214.MATTER SOLUBLE IN HEXANE9. Reagent9.1 HexanePure hexane or commercial hexane or petro-leum ether of boiling point not higher than 75C. Redistillbefore us
16、ing.10. Procedure10.1 Place 100 g of the pigment in an extraction thimble ina Soxhlet extraction apparatus. Record the tare weight of thereceiving flask. Charge the flask with a suitable volume ofhexane and extract the sample for 4 h, subjecting the specimento not less than 20 extractions in this ti
17、me. Make a blankdetermination at the same time.10.2 Remove the receiving flask, evaporate or distill off thehexane on a steam bath, and dry the flask at 105 6 2C for 1h. Cool and weigh.10.3 Calculate the percent of matter soluble in hexane,allowing for any material found in the blank.TOTAL ZINC11. R
18、eagents11.1 Potassium Ferrocyanide, Standard SolutionDissolve22 g of potassium ferrocyanide (K4Fe(CN)63H2O) in waterand dilute to 1 L. To standardize, transfer 0.2 g of metallic zincor freshly ignited zinc oxide (ZnO) to a 400-mL beaker.Dissolve in 10 mL of hydrochloric acid (HCl), sp gr 1.19 and20
19、mL of water. Drop in a small piece of litmus paper, addammonium hydroxide (NH4OH) until slightly alkaline, thenadd HCl until just acid, and then 3 mL more of HCl. Dilute toabout 250 mL with hot water and heat nearly to boiling. Run inthe K4Fe(CN)6solution slowly from a buret, while stirringconstantl
20、y, until a drop tested on a white porcelain plate with adrop of the uranyl indicator solution shows a brown tinge afterstanding 1 min. Do not allow the temperature of the solution tofall below 70C during the titration. Run a blank using thesame amounts of reagents and water as in the standardization
21、.The standardization must be made under the same conditionsof temperature, volume, and acidity as obtained when thesample is titrated. Calculate the strength of the K4Fe(CN)6solution in terms of grams of zinc as follows:Z 5 W/V12 B! (1)where:Z = zinc equivalent of the K4Fe(CN)6solution, g/mL,W = zin
22、c used (or equivalent to the ZnO used), g,V1=K4Fe(CN)6solution required for titration of thestandard, mL, andB =K4Fe(CN)6solution required for titration of theblank, mL.11.2 Uranyl Nitrate Indicator Solution Dissolve5gofuranyl nitrate (UO2(NO3)26H2O) in 100 mL of water.12. Procedure12.1 Transfer 0.2
23、5 g of the sample to a 400-mL beaker,moisten with alcohol, and dissolve in 10 mL of HCl (sp gr1.19) and 20 mL of water.12.2 Continue with the procedure used in standardizing theK4Fe(CN)6solution as described in 10.1, beginning with theaddition of the litmus paper and the adjustment of the aciditywit
24、h NH4OH and HCl.12.3 CalculationCalculate the percent of total zinc, T,asfollows:T 5 V22 B2!Z/S1# 3 100 (2)where:V2=K4Fe(CN)6solution required for titration of thespecimen, mL,B2=K4Fe(CN)6solution required for titration of theblank, mL,Z = zinc equivalent of the K4Fe(CN)6solution, g/mL,andS1= sample
25、 used, g.METALLIC ZINCNOTE 1Sections 12 and 13 cover a rapid method for determiningmetallic zinc, intended for routine analysis. The results are inclined to besomewhat low, and for highest accuracy and particularly for referee tests,the hydrogen evolution method should be used.5NOTE 2Metallic zinc m
26、ay also be determined in accordance with TestMethod D 6580.13. Reagents13.1 Ferric Chloride SolutionPrepare a solution contain-ing 20 g of ferric chloride (FeCl36H2O) and 20 mL of 20 %sodium acetate (NaC2H3O2) solution per 100 mL. It is advis-able to make up only one days supply at a time (50 mL are
27、required for each determination).13.2 Potassium Permanganate, Standard Solution (0.1 N,1mL = 0.008 g TiO2)Dissolve 3.16 g of KMnO4in water anddilute to 1 L. Let stand 8 to 14 days, siphon off the clearsolution (or filter through a medium porosity fritted disk), andstandardize against the National In
28、stitute of Standards andTechnology (NIST) standard chemical No. 40 of sodiumoxalate (Na2C2O4) as follows: In a 400-mL beaker dissolve0.2500 to 0.3000 g of the NIST sodium oxalate in 250 mL ofhot water (80 to 90C) and add 15 mL of H2SO4(1+1). Titrateat once with the KMnO4solution, stirring the liquid
29、 vigorouslyand continuously. The KMnO4must not be added more rapidlythan 10 to 15 mL/min, and the last 0.5 to 1 mL must be addeddropwise with particular care to allow each drop to be fullydecolorized before the next is introduced. The solution shallnot be below 60C by the time the end point has been
30、 reached.(More rapid cooling may be prevented by allowing the beakerto stand on a small hot plate during the titration. The use of asmall nonmercury type thermometer as a stirring rod is mostconvenient.) Keep the KMnO4solution in a glass-stopperedbottle painted black to keep out light, or in a brown
31、 glass bottlestored in a dark place.5Wilson, L. A., “The Evaluation of Zinc Dust: A Proposed Method of Analysis,”Proceedings, ASTEA, Am. Soc. Testing and Mats., Vol 18, Part II, 1918, p. 220.D 521 02 (2007)213.3 Sodium Acetate Solution (200 g/L)Dissolve 200 g ofsodium acetate (NaC2H3O2)or332gofNaC2H
32、3O23H2O, inwater and dilute to 1 L.13.4 Zimmerman-Reinhardt SolutionPrepare a solutioncontaining 67 g of manganese sulfate (MnSO44H2O) 130 mLof H2SO4(sp gr 1.84), and 138 mL of phosphoric acid (H3PO4)(85 %) per L.14. Procedure14.1 Weigh 0.2 g of the sample, transfer immediately to adry, 600-mL heavy
33、-wall Erlenmeyer flask, and add 50 mL ofthe FeCl3solution. Tightly stopper the flask and agitateconstantly for approximately 15 min. As soon as the zinc dustis all dissolved, add 50 mL of the Zimmerman-Reinhardtsolution and 250 mL of water. Titrate with 0.1 N KMnO4solution.NOTE 3If preferred, the re
34、duced iron may be titrated with 0.1 Npotassium dichromate (K2Cr2O7) solution, using sodium diphenylaminesulfonate in the presence of phosphoric acid (H3PO4) as an internalindicator.614.2 BlankMake a blank determination, following thesame procedure and using the same amounts of all reagentsprior to t
35、he titration. (The blank is usually 0.1 to 0.2 mL of 0.1N KMnO4solution.)14.3 CalculationCalculate the percent of metallic zinc,M, as follows:M 5 V32 B3!N 3 0.0327!/S2# 3 100 (3)where:V3= KMnO4solution required for titration of thespecimen, mL,B3= KMnO4solution required for titration of theblank, mL
36、,N = normality of the KMnO4solution,S2= sample used, g, and0.327 = milliequivalent weight of Zn.ZINC OXIDE15. Calculation15.1 Calculate the percent of zinc oxide (ZnO), Z,asfollows:Z 5 A 2 C! 3 1.2447 (4)where:A = total zinc, % (Section 10), andC = metallic zinc, % (Section 12).CALCIUM16. Reagents16
37、.1 Ammonium Oxalate, Saturated SolutionMix 50 g ofammonium oxalate and 1 L of water.16.2 Ammonium Oxalate Solution (10 g/L)Dissolve 10 gof ammonium oxalate in water and dilute to 1 L.16.3 Potassium Permanganate, Standard Solution (0.1N)See 13.2.17. Procedure17.1 Transfer 10 g of the sample, weighed
38、to 0.1 g, to a400-mL beaker. Dissolve in 30 mL of HCl (1 + 1), keeping thebeaker covered. Dilute to 200 mL. The solution at this pointshould be clear and transparent. Neutralize with NH4OH.(Some zinc, because of its high concentration, will precipitateout as hydroxide at this point.) Add NH4OH (sp g
39、r 0.90)dropwise, stirring until the solution becomes clear. Heat nearlyto boiling and add 75 mL of saturated ammonium oxalatesolution. Boil until the precipitate assumes a dense crystallineappearance.Allow to settle on a steam bath for 20 min and thencool. Filter on close-grained paper and wash five
40、 times with acold ammonium oxalate solution (10 g/L).17.2 Carefully dissolve the precipitate from the filter paper,using alternately hot HCl (1+3) and hot water. Catch in a clean400-mL beaker, dilute (if necessary) to a volume of about 250mL, and add 25 mL of saturated ammonium oxalate solution.Brin
41、g to a boil, and add NH4OH in slight excess. Boil until theprecipitate becomes crystalline and dense. Let stand1honasteam bath. Allow to cool. Filter and wash with small amountsof hot water until all ammonium oxalate is removed.17.3 Remove the paper from the funnel and spread it out onthe inside of
42、a 600-mL beaker above 300 mL of warm water towhich has been added 20 mL of H2SO4(1+1). Rinse theprecipitate off the paper with water from a wash bottle andwarm the solution to 80C. Titrate at this temperature withKMnO4solution. As soon as a persistent pink end point isobtained, drop the paper into t
43、he liquid, rinse the side of thebeaker, and quickly complete the titration.17.4 CalculationCalculate the percent of calcium, C,asCaO, as follows:C 5 V4N 3 0.02804!/S3# 3 100 (5)where:V4= KMnO4solution required for titration of the sample,mL,N = normality of the KMnO4solution, andS3= specimen used, g
44、.LEAD18. Procedure18.1 Determine the lead content in accordance with Section6 of Test Method E40.NOTE 4Lead may also be determined in accordance with Test MethodE68.IRON19. Procedure19.1 Determine the iron content in accordance with Section22 of Test Method E40.CADMIUM20. Procedure20.1 Determine the
45、 cadmium content in accordance with18.1 and 18.3 of Test Method E40.6Kolthoff, I. M., and Sandell, E. B., Textbook of Quantitative Inorganic Analysis,1945, p. 608.D 521 02 (2007)3NOTE 5Cadmium may also be determined in accordance with TestMethod E68.CHLORINE21. Reagents21.1 Silver Nitrate Solution (
46、3.5 g/L)Dissolve 3.5 g ofsilver nitrate (AgNO3) in water and dilute to 1 L.21.2 Sodium Chloride, Standard Solution (0.01 N)Dissolve 0.5850 g of pure sodium chloride (NaCl) in water anddilute to 1 L.22. Procedure22.1 Transfer 1.000 g of the sample to a 200-mL electrolyticbeaker. Add 20 mL of water an
47、d then cautiously add 5 mL ofnitric acid (HNO3) (sp gr 1.42). Cover with a watch glass andheat on a steam bath with frequent stirring for 5 min, or untila clear solution results. Add 70 mL of water and cool to roomtemperature.22.2 To the specimen and to a blank (prepared in similarfashion) add 5.0 m
48、L of AgNO3solution (3.5 g/L) and stir. Tothe blank, add dropwise from a 10-mL buret, with thoroughmixing, enough NaCl solution to develop a turbidity matchingthat of the sample. Keep the contents of both beakers wellstirred and view against a black background in equal illumi-nation.22.3 CalculationC
49、alculate the percent of chlorine, C,asfollows:C 5 0.035 V5(6)where V5= 0.01 N NaCl solution added to the blank, mL.SULFUR23. Reagents23.1 Barium Chloride Solution (100 g/L)Dissolve 117 gof barium chloride (BaCl22H2O) in water and dilute to 1 L.23.2 Bromine Water (saturated).24. Procedure24.1 Transfer 20 g of the specimen, weighed to the nearest0.1 g, to a 600-mL beaker. Cover the sample with 50 mL ofsaturated bromine water and then cautiously add HNO3(sp gr1.42) until solution is complete.24.2 Add 1 g of anhydrous sodium carbonate (Na2
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