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分子筛催化材料设计与制备MethodsCharacterizationInstancesBackgroundDefinitionMolecularsieveisakindofmaterialhasauniformporesize,whichisequivalenttotheaveragesizeofthemolecule.Developmenthistory•In1756,peoplefirstdiscoverednaturalzeolites.•In19thcentury,peoplehadafurtherunderstandingofthemicroporousproperties,adsorptionandionexchange.•In1940s,zeolitechemistledbyBarrerRMfirstlysynthesislowsilicaaluminaratioofzeolitemolecularsieve.Developmenthistory020406080100120140160197019781988199620012003MicroporousstructuretypesbyIZAtypeszeolitemicroporemesporousmacroporeClassification＜2nm2~50nm＞50nmApplicationMainproperties•Adsorptionperformance•Ionexchangeperformance•CatalyticperformanceMainapplicationareas•Petroleumprocessing•Petroleumchemicalindustry•Finechemical•DailychemicalindustryProspects•FCC:ExploitnewzeolitessimilartoZSM-5withhighselectivitytowardsproducelightolefins•HDC:Exploitprolificmiddledistillateszeolites•Aliphaticalkylation•Isomerizationofalkanes•OthervarietiesdevelopmentStructure(a)TO4tetrahedron(b)TO4tetrahedronshareoneoxygenvertexPrimarystructuralunitsMolecularsieveiscomposedofthree-dimensionalfourconnectingframebythesharedvertexoftheTO4tetrahedron.TusuallyreferstoSi,Al,orP.InrarecasesTreferstoB,Ga,Beandsoon.Structure•Aluminosilicatemolecularsieveconsistedof[SiO4]and[AlO4]tetrahedroncontainsbackboneanion,thenegativelychargeofbackbonearebalancedwithadditionalcations.•Aluminosilicatemolecularsieve’schemistrygeneralformulaisAx/n(SiO2)(AlO2)x·mH2O.StructureSecondarystructuralunitsThebackboneofmolecularsievecouldbeseenascomposedoffiniteelementunitorinfiniteelementunit.Thepictureshows18finiteelementunitsoftetrahedrabackbone.StructureCharacteristiccagetypestructureunitSomecharacteristicsofcagetypestructuralunitsareexistedincharacteristiccagetypestructureunit.CagetypestructureunitinmolecularsievebackboneStructureFeaturesofthechainandlayeredstructureunitsIntheskeletonstructureofmolecularsieve,wecanfindsomeofthefeaturesofthechainstructureunit.StructureFeaturesofthechainandlayeredstructureunitsStructureofmolecularsievecanalsobedescribedbytwo-dimensionalthreeconnectednetworklayer.Theskeletonstructureofthree-dimensionalfourconnectedcouldbeseenasparallelaccumulationtwo-dimensionalthreeconnectedlayerinterconnectedbyupperandlowerorientation.Severalcommontwo-dimensionalthreeconnectednetworklayerCharacterizationThechemicalandphysicalpropertiesofmolecularsievesarecloselyrelatedtothestructureofthematerials.Scientistsstudiedinsynthesis,modificationandapplicationofmolecularsieveneeddetailedstructureandperformanceknowledgetoachievetheirobjectives.Therefore,inthestudyofmolecularsieve,thecharacterizationofthestructureandperformanceisveryimportant.CharacterizationAnalyticalmethodDiffractionSpectrumMicroscopictechniqueAdsorption,desorption,thermalanalysistechniqueCharacterizationDiffraction:Themosteffectivemethodtostudythelonghistorystructureofcrystalmaterials.Typesofradiationsourceswidelyusedinstructureresearchconcludeelectrondiffraction,diffraction,Xraydiffractionandsynchrotronradiationsources.Spectrum:Spectroscopictechniqueisthestudyofatomicandmolecularphysicsprocess,whichisbasedonatomicormolecularabsorption,emissionandscatteringofelectromagneticwaves.ForexampleIR,Ramanspectroscopy,EELS,IETS,INSS.CharacterizationMicroscopictechnique:usingopticaldevicestoobtainanenlargedimageofanobject.ForexampleSEM,TEM,STM.Adsorption,desorption,thermalanalysistechnique:usingadsorptionanddiffusionexperiments,programdesorption,,thermalanalysis,catalyticreactiontestofprobemoleculestogetsurfacestructureinformationindirectly.CharacterizationPropertycharacterizationbackbonepartscavitypartsBackboneparts:•Structure•Chemicalcomposition•Impurity•StructuraldefectsCavityparts:•Porevolume•Specificsurfacearea•Poresizedistribution•CavityshapeBraggEquationWhenX-ray(Wavelengthλ)incidenttoanylatticeplane,Inthelatticeplane,eachlatticepointincidentwavescatteringangleandthereflectionangleisequal,theX-ray,X-rayandantisurfacenormalsinthesameplane.WhenThelatticeplanewavescatteringopticalpathdifferenceisanintegermultipleofthewavelength,Theyhavethesamephase,thescatteringwavesuperpositionreinforceeachother,resultingindiffraction.XRDXRDThebasicstructurediagramofXraydiffractionA.AimingdeviceB.SampleC.SlitD.MonochromatorE.DetectorX.XraysourceXRDHighstabilityXraysourceisprovidedtomeasuretherequiredXraysAdjustmentmechanismsystemofsampleandsamplepositionorientationProcessingandanalysissystemofdiffractionpatternRaydetectorAdsorptionManypropertiesofcavitiesaredeterminedbyphysicaladsorption.N2,ArorO2wasalwaysusedasadsorbatesothatwecanmeasureporevolume,specificsurfacearea,poresizedistributionofporousmaterial.mesoporousmaterialstypeⅠmicroporousmaterialsultraporousmaterialstypeⅡtypeⅣmacroporousmaterialtypeⅥAdsorptionAdsorptionAdsorptionequilibriumisothermClassificationofadsorptionisothermsbyIUPACAdsorptionHysteresisIftheadsorption-desorptionisnotcompletelyreversible,theadsorption-desorptionisothermsarenotcoincident.ThisphenomenonmainlyoccurredintypeⅣadsorptionequilibriumisotherm.AdsorptionFo