Designation:D7881−20´1StandardTestMethodforDeterminationof4-Carboxybenzaldehydeandp-ToluicAcidinPurifiedTerephthalicAcidbyCapillaryElectrophoresiswithReverseVoltageMode1ThisstandardisissuedunderthefixeddesignationD7881;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ε1NOTE—ResearchreportinformationinSection14wasupdatededitoriallyinFebruary2021.1.Scope*1.1Thistestmethod2coversthedeterminationof4-carboxybenzaldehyde(4-CBA)andp-toluicacid(p-TOL)inpurifiedterephthalicacid(PTA)bycapillaryelectrophoresis(CE)withreversevoltagemodeandUVdetection.Itisapplicablefor4-CBAfrom3to400mg/kgandforp-TOLfrom8to400mg/kg,respectively.1.2Indeterminingtheconformanceofthetestresultsusingthismethodtoapplicablespecification,resultsshallberoundedoffinaccordancewiththerounding-offmethodofPracticeE29.1.3ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafety,health,andenvironmentalpracticesanddeter-minetheapplicabilityofregulatorylimitationspriortouse.1.5Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.ReferencedDocuments2.1ASTMStandards:3D1193SpecificationforReagentWaterD6809GuideforQualityControlandQualityAssuranceProceduresforAromaticHydrocarbonsandRelatedMa-terialsE29PracticeforUsingSignificantDigitsinTestDatatoDetermineConformancewithSpecificationsE691PracticeforConductinganInterlaboratoryStudytoDeterminethePrecisionofaTestMethod2.2ISODocuments...
