Designation:D3942−03(Reapproved2013)StandardTestMethodforDeterminationoftheUnitCellDimensionofaFaujasite-TypeZeolite1ThisstandardisissuedunderthefixeddesignationD3942;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoversthedeterminationoftheunitcelldimensionofzeoliteshavingthefaujasitecrystalstructure,includingsyntheticYandXzeolites,theirmodificationssuchasthevariouscationexchangeforms,andthedealuminized,decationated,andultrastableformsofY.Thesezeoliteshavecubicsymmetrywithaunitcellparameterusuallywithinthelimitsof24.2and25.0Å(2.42and2.50nm).1.2Thesamplesincludezeolitepreparationinthevariousforms,andcatalystsandadsorbentscontainingthesezeolites.Thezeolitemaybepresentinamountsaslowas5%,suchasinacrackingcatalyst.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2E691PracticeforConductinganInterlaboratoryStudytoDeterminethePrecisionofaTestMethod3.SummaryofTestMethod3.1AsampleofthezeoliteYorX,orcatalystcontainingzeoliteismixedwithpowderedsilicon.ThezeoliteunitcelldimensioniscalculatedfromtheX-raydiffractionpatternofthemixture,usingthesiliconreflectionsasareference.4.SignificanceandUse4.1ZeolitesYandX,particularlyforcatalystandadsorbentapplications,areamajorarticleofmanufactureandcommerce.Catalystsandadsorbentscomprisingthesezeolitesinvariousformsplusbinderandothercomponentshavelikewisebecomeimportant.Y-basedcatalystsareusedforfluidcatalyticcrack-ing(FCC)andhydrocrackingofpetroleum,whileX-basedadsorbentsareusedfordesiccation,sulfurcompoundremoval,andairseparation.4.2Theunitcelldimensionofafreshlysynthesizedfauj...
