Designation:D2350−90(Reapproved2015)StandardTestMethodforAntimonyOxideinWhitePigmentSeparatedFromSolvent-ReduciblePaints1ThisstandardisissuedunderthefixeddesignationD2350;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheU.S.DepartmentofDefense.1.Scope1.1Thistestmethodcoversthedeterminationofthetotalantimonyoxideinwhitepigmentseparatedfromsolvent-reduciblepaints.1.2ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2D1193SpecificationforReagentWaterD2371TestMethodforPigmentContentofSolvent-ReduciblePaints3.SummaryofTestMethod3.1Thepigmentisdissolvedinhydrochloricacid(HCl).Sulfuricacid(H2SO4)isadded.Themixtureistitratedwithpotassiumpermanganate(KMnO4)andcalculatedtoantimonyoxide(Sb2O3)whichgivesantimonyintheouscondition.3.2ThepigmentisdissolvedinH2SO4withpotassiumsulfate(K2SO4)andreduced.Sodiumsulfite(Na2SO3)isaddedandsulfurdioxidegas(SO2)isexpelled.ThesolutionisdilutedandHCladdedafterwhichthesolutionistitratedwithKMnO4,whichgivestotalantimonycalculatedtoSb2O3.3.3Sb2O3fromousconditionissubtractedfromtotalSb2O3andresidualSb2O3iscalculatedtoSb2O5.3.4Theprocedureisalsodescribedforantimonyoxideinpresenceoflargeamountsofiron.4.SignificanceandUse4.1Antimonytrioxideisoftenusedinfire-retardantpaints,soitisusefultoformulatorsanduserstobeabletomonitortheamountofthiscompoundinwholepaints.5.Reagents5.1PurityofReagents—Reagentgradechemicalsshallbeusedinalltests.Unlessotherwiseindicated,itisintendedtha...
