Designation:D2930–03StandardTestMethodforMaleicAcidinMaleicAnhydridebyPotentiometricTitration1ThisstandardisissuedunderthefixeddesignationD2930;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoversthedeterminationoffreemaleicacidinrefinedmaleicanhydridebypotentiometrictitration.1.2Thistestmethodisapplicableforallconcentrationsofmaleicacid;however,itisprimarilyusedforconcentrationsbelow0.5%.1.3Thefollowingappliestoallspecifiedlimitsinthisstandard:Forpurposesofdeterminingconformancewiththisstandard,anobservedvalueoracalculatedvalueshallberoundedoff“tothenearestunit”inthelastright-handdigitusedinexpressingthespecificationlimit,inaccordancewiththerounding-offmethodofPracticeE29.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.Forspecifichazardstatements,seeSection7.2.ReferencedDocuments2.1ASTMStandards:D1193SpecificationforReagentWater2D3438PracticeforSamplingandHandlingNaphthalene,MaleicAnhydride,andPhthalicAnhydride3E29PracticeforUsingSignificantDigitsinTestDatatoDetermineConformancewithSpecifications42.2OtherDocuments:OSHARegulations,29CFR,paragraphs1910.1000and1910.1200.53.SummaryofTestMethod3.1Thistestmethodisbasedonadirecttitrationofmaleicacidusingatertiaryamineasthebase.Thetitrationiscarriedoutinananhydroussolventsystemandfollowedpotentio-metricallybymeansofapHmeter.Tertiaryaminesdonotreactwithanhydrides.Onlyonecarboxylicacidgroupistitrated.4.SignificanceandUse4.1Themaleicacidcontentisusuallyanindicationofexposuretomoistureinair.Maleicanhydridereactswithmoisturetoformmaleicacid.5.Apparatus5.1TitrimeterorpHmeter,equippedwithglassandcalomele...
