Designation:D7736−12StandardTestMethodforDeterminationofAcidsandGlycolEstersinEthyleneGlycol1ThisstandardisissuedunderthefixeddesignationD7736;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoversthedeterminationoffreeacidsandglycolestersinethyleneglycolbytitration.1.2Thistestmethodisforusedonethyleneglycolusedforthemanufactureofenginecoolant.Itcannotbeusedonformulatedenginecoolant.Theinhibitorswillinterferewiththedetermination.1.3ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2D1176PracticeforSamplingandPreparingAqueousSolu-tionsofEngineCoolantsorAntirustsforTestingPurposesD1193SpecificationforReagentWaterD4725TerminologyforEngineCoolantsandRelatedFluidsE177PracticeforUseoftheTermsPrecisionandBiasinASTMTestMethodsE691PracticeforConductinganInterlaboratoryStudytoDeterminethePrecisionofaTestMethod3.Terminology3.1Definitions:3.1.1Fordefinitionsoftermsusedinthistestmethod,refertoTerminologyD4725.4.SummaryofTestMethod4.1Thistestmethodisusedtodeterminetheacidandestercontentofethyleneglycolbytitration.Thesampleistitratedtothephenolphthaleinendpointwith0.02NNaOHtodeterminetheacidity.Thenaknownamountofbaseisaddedandthesampleisheatedat100°Ctohydrolyzetheesters.Itisthenback-titratedwith0.02Nsulfuricacidtodeterminetheestercontent.5.SignificanceandUse5.1Thepresenceofacidsorglycolestersintheethyleneglycolusedtoproduceenginecoolantisundesirable.Underconditionsinanenginecoolingsystem,theesterscanhydro-lyzetoformglycola...
