ASTM_D_284_-_88_1999.pdf

Designation:D 284 88(Reapproved 1999)Standard Test Methods forChemical Analysis of Mercuric Oxide Pigment1This standard is issued under the fixed designation D 284;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(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 These test methods cover procedures for the chemicalanalysis of mercuric oxide pigment.1.2 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.A specific hazardstatement is given in the Note 1 of 11.1.2.Referenced Documents2.1 ASTM Standards:D 1193 Specification for Reagent Water2D 1208 Test Methods for Common Properties of CertainPigments33.Significance and Use3.1 These test methods are intended as a quick and reliableprocedure for measuring purity of mercuric oxide pigment todetermine if it meets purity standards as agreed upon betweenthe producer and the consumer.4.Purity of Reagents and Materials4.1 Reagent grade chemicals shall be used in all tests.Unless otherwise indicated,it is intended that all reagents shallconform to the specifications of the Committee on AnalyticalReagents of the American Chemical Society,where suchspecifications are available.4Other grades may be used,pro-vided it is first ascertained that the reagent is of sufficientlyhigh purity to permit its use without lessening the accuracy ofthe determination.4.2 Unless otherwise indicated,references to water shall beunderstood to mean reagent water conforming to Type II ofSpecification D 1193.5.Preparation of Sample5.1 If the sample is large,mix it thoroughly before taking arepresentative portion.Grind the representative portion to afine powder and thoroughly mix before taking portions foranalysis.Keep the sample in a stoppered glass bottle.6.Precision6.1 Repeatability and reproducibility are believed to be wellwithin the limits usually obtained on similar chemical testmethods,but no actual figures on precision are available.ALKALINITY OR ACIDITY7.Procedure7.1 Determine alkalinity or acidity in accordance with TestMethods D 1208.FREE MERCURY8.Procedure8.1 Examine a representative specimen of the dry mercuricoxide under a microscope for the presence of free mercury.TOTAL MERCURY9.Reagents and Materials9.1 AmmoniumThiocyanate,StandardSolution(1mL 5 0.012 g Hg)Dissolve 9 g of ammonium thiocyanate(NH4CNS)in water and dilute to 1 L.Standardize the solutionagainst mercury,as follows:Weigh to 0.1 mg about 4.6 g ofmercury,and dissolve it in 40 mL of warm HNO3(1+1).Diluteto 200 mL with water and add KMnO4solution(50 g/L)dropwise until the pink color persists for 5 min in order toensure the absence of nitrous acid(HNO2)and monovalentmercury.Add FeSO4solution(50 g/L)dropwise to destroyexcess permanganate.Add 4 mL of ferric ammonium sulfateindicator solution,and titrate with the NH4CNS solution.9.2 Calculate the mercury equivalent M of the NH4CNSsolution,in grams per millilitre,as follows:M 5 W1/V1where:W15 mercury used,g,andV15 NH4CNS solution required for titration,g.9.3 Ferric Ammonium Sulfate Indicator SolutionDissolveenough ferric ammonium sulfate(Fe2(SO4)3(NH4)2SO424H1These test methods are under the jurisdiction ofASTM Committee D-1 on Paintand Related Coatings,Materials,and Applications and are the direct responsibilityof Subcommittee D 01.31 on Pigment Specifications.Current edition approved Oct.31,1988.Published December 1988.Originallypublished as D 284 28 T.Last previous edition D 284 74(1987)e1.2Annual Book of ASTM Standards,Vol 11.01.3Annual Book of ASTM Standards,Vol 06.03.4Reagent 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.1AMERICAN SOCIETY FOR TESTING AND MATERIALS100 Barr Harbor Dr.,West Conshohocken,PA 19428Reprinted from the Annual Book of ASTM Standards.Copyright ASTMNOTICE:This standard has either been superceded and replaced by a new version or discontinued.Contact ASTM International(www.astm.org)for the latest information.2O)in water to make a saturated solution at room temperatureand add HNO3(sp gr 1.42)dropwise to bleach the brown colorof the solution.About 30 g of ferric ammonium sulfate per 100mL of water will be required for the saturated solution.9.4 Ferrous Sulfate Solution(50 g/L)Dissolve 5 g offerrous sulfate(FeSO47H2O)in water and dilute to 100 mL.9.5 Nitric Acid(sp gr 1.42)Concentrated nitric acid(NHO3).9.6 Nitric Acid(1+1)M