Designation:D4654−87(Reapproved2015)StandardTestMethodforSulfateBasicityinLeather1ThisstandardisissuedunderthefixeddesignationD4654;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodisintendedforuseincalculatingthesulfatebasicityofmineraltannedleather.1.2Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2D2807TestMethodforChromicOxideinLeather(Perchlo-ricAcidOxidation)D4655TestMethodsforSulfatesinLeather(Total,Neutral,andCombinedAcid)3.SignificanceandUse3.1Thistestmethodisusedtodeterminethepercentoftotalchromicoxidethatiscombinedwithhydroxylandmayserveasameasureofchromefixation.4.ApparatusandReagents4.1TheapparatusandreagentsshallbeasdescribedinTestMethodsD2807andD4655.5.Sampling,TestSpecimensandTestUnits5.1ThetestspecimenshallbeasdescribedinTestMethodsD2807andD4655.5.2Unlessotherwisespecifiedinthedetailspecifications,twospecimensfromthecompositesampleshallbetested.5.3Thepercentbasicityofthesamplefortestshallbetheaverageofthetestresultsobtainedfromthespecimenstested.6.Procedure6.1ThechromicoxideshallbedeterminedasdescribedinTestMethodD2807.ThecombinedsulfateshallbedeterminedasdescribedinMethodD4655.7.CalculationofResults7.1ExpressthepercentbasicityofthespecimenaccordingtoSchorlemmer’ssystem.Inthissystem,thepercentbasicityisthepercentofthetotalchromicoxidethatiscombinedwithhydroxyl.Conversely,thepercentacidityisthepercentofthetotalchromicacidthatiscombinedwithsulfateorotheracidanions.Percentbasicityistherefore100%acidity.sulfatebasicity,%51002%combinedsulfate352.8/%totalchromicoxide(1)7.2Whenothermetalsthatformhy...
