ASTM_D_444_-_88_2014.pdf

Designation:D44488(Reapproved 2014)Standard Test Methods forChemical Analysis of Zinc Yellow Pigment(Zinc ChromateYellow)1This standard is issued under the fixed designation D444;the number immediately following the 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()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 These test methods cover procedures for the chemicalanalysis of the pigment known commercially as“zinc yellow”or“zinc chromate yellow.”1.2 The analytical procedures appear in the following order:SectionsMoisture and Other Volatile Matter7Combined Water8Chromium:Dichromate Method9 11Thiosulfate Method9,12,and 13Zinc:Hydroxyquinoline Method9,14,and 15Ferrocyanide Method9,16,and 17Alkaline Salts18 and 19Sulfates20 and 21Chlorides22 and 23Matter Insoluble in Dilute AceticAcid24Coarse Particles251.3 The values stated in SI units are to be considered thestandard.The values given in parentheses are for informationonly.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 determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D185 Test Methods for Coarse Particles in PigmentsD280 Test Methods for Hygroscopic Moisture(and OtherMatter Volatile Under the Test Conditions)in PigmentsD478 Specification for Zinc Yellow(Zinc Chromate)Pig-mentsD1193 Specification for Reagent WaterE11 Specification for Woven Wire Test Sieve Cloth and TestSievesE50 Practices for Apparatus,Reagents,and Safety Consid-erations for Chemical Analysis of Metals,Ores,andRelated Materials3.Significance and Use3.1 This test method has been developed to standardize thechemical analysis of zinc chromate yellow pigment and toprovide alternate methods of analysis for chromium and zinc.4.Preparation of Sample4.1 Mix the laboratory sample thoroughly.Take a sufficientquantity for the chemical analyses and pass it through a180-m(No.80)sieve,grinding in a mortar if necessary.NOTE1Detailed requirements for this sieve are given in SpecificationE11.5.Reagents5.1 Purity of ReagentsUnless otherwise indicated,it isintended that all reagents shall conform to the specifications ofthe Committee onAnalytical Reagents of theAmerican Chemi-cal Society,where such specifications are available.3Othergrades may be used,provided it is first ascertained that thereagent is of sufficiently high purity to permit its use withoutlessening the accuracy of the determination.5.2 Purity of WaterUnless otherwise indicated,referencesto water for use in the preparation of reagents and in analyticalprocedures shall conform to Type II reagent water,in Specifi-cation D1193.1These 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 Pigment Specifications.Current edition approved Dec.1,2014.Published December 2014.Originallyapproved in 1937.Last previous edition approved in 2008 as D444 88(2008).DOI:10.1520/D0444-88R14.2For referenced ASTM 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.3Reagent Chemicals,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 Formulary,U.S.Pharmacopeial Convention,Inc.(USPC),Rockville,MD.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.Precision6.1 Precision statements have not been established.MOISTURE AND OTHER VOLATILE MATTER7.Procedure7.1 Determine moisture and other volatile matter in accor-dance with Test Method A of Test Methods D280.COMBINED WATER8.Procedure8.1 Weigh to 0.1 mg 3 g of the oven-dried material from thedetermination of moisture and other volatile matter(Note 2 andNote 3),and place in a porcelain boat.Introduce the boat withthe charge into a refractory combustion tube in an electrically-heated combustion furnace of the type used for the determina-tion of carbon in steel by direct combustion(Note 4).Place theboat at the center of the combustion tube maintained at atemperature of 1000C for 4 h.Draw a current of pure dry airor dry nitrogen through the tube to sweep the evolved moistureinto a previously weighed absorption tube containing anhy-drous magnesium perchlorate(Mg(ClO4)2)or other efficientdesiccan