Designation:D524−15Designation:14/94StandardTestMethodforRamsbottomCarbonResidueofPetroleumProducts1ThisstandardisissuedunderthefixeddesignationD524;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheU.S.DepartmentofDefense.1.Scope*1.1Thistestmethodcoversthedeterminationoftheamountofcarbonresidue(Note1)leftafterevaporationandpyrolysisofanoil,anditisintendedtoprovidesomeindicationofrelativecoke-formingpropensity.Thistestmethodisgenerallyapplicabletorelativelynonvolatilepetroleumproductswhichpartiallydecomposeondistillationatatmosphericpressure.Thistestmethodalsocoversthedeterminationofcarbonresidueon10%(V/V)distillationresidues(seeSection10).Petroleumproductscontainingash-formingconstituentsasdeterminedbyTestMethodD482,willhaveanerroneouslyhighcarbonresidue,dependingupontheamountofashformed(Notes2and3).NOTE1—Thetermcarbonresidueisusedthroughoutthistestmethodtodesignatethecarbonaceousresidueformedduringevaporationandpyrolysisofapetroleumproduct.Theresidueisnotcomposedentirelyofcarbon,butisacokewhichcanbefurtherchangedbypyrolysis.Thetermcarbonresidueiscontinuedinthistestmethodonlyindeferencetoitswidecommonusage.NOTE2—ValuesobtainedbythistestmethodarenotnumericallythesameasthoseobtainedbyTestMethodD189,orTestMethodD4530.Approximatecorrelationshavebeenderived(seeFig.X2.1)butneednotapplytoallmaterialswhichcanbetestedbecausethecarbonresiduetestisapplicabletoawidevarietyofpetroleumproducts.TheRamsbottomCarbonResiduetestmethodislimitedtothosesamplesthataremobilebelow90°C.NOTE3—Indieselfuel,thepresenceofalkylnitratessuchasamylnitrate,hexylnitrate,oroctylnitrate,causesahighercarbonresiduevaluethanobservedinuntreatedfuel,whichcanleadtoerroneousconclusionsastothecoke-formingpropensityofthefuel.Thepresenceofalkylnitrateint...
