Designation:D7621−15aIP570StandardTestMethodforDeterminationofHydrogenSulfideinFuelOilsbyRapidLiquidPhaseExtraction1,2ThisstandardisissuedunderthefixeddesignationD7621;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thistestmethodcoversprocedures(AandB)forthedeterminationofthehydrogensulfide(H2S)contentoffueloilssuchasmarineresidualfuelsandblendstocks,withviscosityupto3000mm2s-1at50°C,andmarinedistillatefuels,asmeasuredintheliquidphase.NOTE1—Specificationfuelsfallingwithinthescopeofthistestmethodare:ASTMSpecificationD396,MIL-DTL-16884,andISO8217.1.2ProcedureAhasbeenshowntoeliminateinterferencessuchasthiols(mercaptans)andalkylsulfides.ProcedureBcangiveelevatedresultsifsuchinterferencesarepresent(seeAnnexA2).NOTE2—AprocedureformeasuringtheamountofhydrogensulfideincrudeoilcanbefoundinAppendixX1.FullprecisionforAppendixX1hasnotyetbeendetermined.1.3ValidrangesfortheprecisionaregiveninTable2andTable3.Measurementscanbemadeoutsidetheserangeshoweverprecisionhasnotbeendetermined.1.4SamplescontainingFAMEdonotaffectthemeasure-mentofhydrogensulfidebythistestmethod.1.5ThevaluesstatedinSIunitsaretoberegardedasstandard.Non-SIunitsgiveninparenthesesareforinformationonly.1.6Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:3D396SpecificationforFuelOilsD4057PracticeforManualSamplingofPetroleumandPetroleumProductsD5705TestMethodforMeasurementofHydrogenSulfideintheVaporPhaseAboveResidualFuelOilsD6021TestMethodforMeasurementofTotalHydrogenSulfideinResidualFuelsbyMultipleHeadspaceExtrac-tionandSulfurSpecificDetectionD6300PracticeforDeterminati...
