Designation:D6019−15TestMethodforDeterminationofChromicOxideinBasicChromiumTanningLiquors(AmmoniumPersulfateOxidation)1ThisstandardisissuedunderthefixeddesignationD6019;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoversthedeterminationofchromicoxideinchrometanningliquors,eithersimple,withaddedaluminumorzirconium,orwiththeusualmaskingcomplexingagents.1.2ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.SummaryofTestMethod2.1Thesolutionisoxidizedwithammoniumpersulfateuntilthechromiumiscompletelyconvertedtothechromateion.Thesolutionisboiledtocompleteoxidationoforganicmaterialsandtodestroyexcessammoniumpersulfate;itisthencooledandacidified.Potassiumiodideisadded,andtheliberatediodineistitratedwithstandardizedsodiumthiosul-fate.3.SignificanceandUse3.1Theproceduredescribedisforthequalitycontrolformanufacturingliquorsandspecificationsforthepurchaseofsuchliquors.3.2Thechromiumcontentoftheliquorsdeterminestheamounttobeusedtoobtainthedesireddegreeoftannage,andhencemaybeamatterforspecificationinthepurchaseofleather.4.ReagentsandMaterials4.1PurityofReagents—Reagentgradechemicalsshallbeusedinalltests.Unlessotherwiseindicated,itisintendedthatallreagentsshallconformtothespecificationsoftheCommit-teeonAnalyticalReagentsofTheAmericanChemicalSociety,wheresuchspecificationsareavailable.2Othergradesmaybeused,provideditisfirstascertainedthatthereagentisofsufficientlyhighpuritytopermititsusewithoutlesseningtheaccuracyofthedetermination.4.2PurityofWater—Unlesso...
