分子筛催化材料

1、ITL分子筛催化材料设计与制备BackgroundCharacterizationMethodsInstancesBackgroundDefinitionMolecularsieveisakindofmaterialhasauniformporesize,whichisequivalenttotheaveragesizeofthemolecule.DevelopmenthistoryIn1756,peoplefirstdiscoverednaturalzeolites.In19thcentury,peoplehadafurtherunderstandingofthemicroporouspro

2、perties,adsorptionandionexchange.In1940s,zeolitechemistledbyBarrerRMfirstlysynthesislowsilicaaluminaratioofzeolitemolecularsieve.50nmClassificationzeolitemicropore1mesporousmacroporeApplicationMainpropertiesMainapplicationareasAdsorptionperformancePetroleumprocessingIonexchangeperformancePetroleumch

3、emicalindustryCatalyticperformanceFinechemicalDailychemicalindustryProspectsFCC:ExploitnewzeolitessimilartoZSM-5withhighselectivitytowardsproducelightolefinsHDC:ExploitprolificmiddledistillateszeolitesAliphaticalkylationIsomerizationofalkanesOthervarietiesdevelopmentStructureTO4tetrahedronTO4tetrahe

4、dronshareoneoxygenvertexPrimarystructuralunitsMolecularsieveiscomposedofthree-dimensionalfourconnectingframebythesharedvertexoftheTO4tetrahedron.TusuallyreferstoSi,Al,orP.InrarecasesTreferstoB,Ga,Beandsoon.AluminosilicatemolecularsieveconsistedofSiO4andA1O4tetrahedroncontainsbackboneanion,thenegativ

5、elychargeofbackbonearebalancedwithadditionalcationsAluminosilicatemolecularsieveschemistrygeneralformulaisAx/n(SiO2)(AlO2)x-mH2OStructureStructure4SecondarystructuralunitsThebackboneofmolecularsievecouldbeseenascomposedoffiniteelementunitorinfiniteelementunit.3C2UPThepictureshows18finiteelementunits

6、oftetrahedrabackboneCharacteristiccagetypestructureunitSomecharacteristicsofcagetypestructuralunitsareexistedincharacteristiccagetypestructureunit.DOoCagetypestructureunitinmolecularsievebackboneNo.3No.5细D6R)No.114呻現備No.124WNa.84VNo.13fillNo.9No.144*5WNa04WNo.15No.18屮智（陀妁SV4MWK8V/ew)No.2742十*6咕丄A*Mo

7、,104WNo3l6伽No.324*妝帑加，No28No.29WsW(dar)4m64123No.355峽伽）Nd44才6灯Ng.45No.46率4打圧萨承Ho.424l4,4j4W6;828282Nck47No.4JNM4忖曲励Wo4444*6阴No.49MU愀伽）Nq514VW制No.554lWL2l(Any)No.%曲4附計No.574J4*4u6e12,i23No,533先g/No.59464,W2tNo.60No.61户帕12ommuhou油StructureFeaturesofthechainandlayeredstructureunitsIntheskeletonstructur

8、eofmolecularsieve,wecanfindsomeofthefeaturesofthechainstructureunit.StructureFeaturesofthechainandlayeredstructureunitsStructureofmolecularsievecanalsobedescribedbytwo-dimensionalthreeconnectednetworklayer.Theskeletonstructureofthree-dimensionalfourconnectedcouldbeseenasparallelaccumulationtwo-dimen

9、sionalthreeconnectedlayerinterconnectedbyupperandlowerorientation.Severalcommontwo-dimensionalthreeconnectednetworklayerCharacterizationThechemicalandphysicalpropertiesofmolecularsievesarecloselyrelatedtothestructureofthematerials.Scientistsstudiedinsynthesis,modificationandapplicationofmolecularsie

10、veneeddetailedstructureandperformanceknowledgetoachievetheirobjectivesTherefore,inthestudyofmolecularsieve,thecharacterizationofthestructureandperformanceisveryimportant.Diffraction:ThemosteffectivemethodtostudythelonghistorystructureofcrystalmaterialsTypesofradiationsourceswidelyusedinstructurerese

11、archconeludeelectrondiffraction,diffraction,XraydiffractionandsynchrotronradiationsourcesSpectrum:Spectroscopictechniqueisthestudyofatomicandmolecularphysicsprocess,whichisbasedonatomicormolecularabsorption,emissionandscatteringofelectromagneticwavesForexampleIR，Ramanspectroscopy，EELS，IETS，INSSMicro

12、scopictechnique:usingopticaldevicestoobtainanenlargedimageofanobject.ForexampleSEM.TEM.STM.Adsorption,desorption,thermalanalysistechnique:usingadsorptionanddiffusionexperiments,programdesorption,5thermalanalysis,catalyticreactiontestofprobemoleculestogetsurfacestructureinformationindirectly.Property

13、characterizationbackbonepartscavitypartsBackboneparts:StructureChemicalcompositionImpurityStructuraldefectsCavityparts:PorevolumeSpecificsurfaceareaPoresizedistributionCavityshapeXRDBraggEquationWhenX-ray(WavelengthX)incidenttoanylatticeplane,Inthelatticeplane,eachlatticepointincidentwavescatteringa

14、ngleandthereflectionangleisequal,theX-ray,X-rayandantisurfacenormalsinthesameplane.When2dh1/=nAThelatticeplanewavescatteringopticalpathdifferenceisanintegermultipleofthewavelength,Theyhavethesamephase,thescatteringwavesuperpositionreinforceeachother,resultingindiffraction.XRDThebasicstructurediagram

15、ofXraydiffractionAimingdeviceSampleSlitMonochromatorDetectorX.XraysourceXRDHighstabilityXraysourceisprovidedtomeasurethequiredXraysAdjustmentmechanismsystemofsampleandsamplepositioorientationProcessingandanalysissystemofdiffractionpatternAdsorptionManypropertiesofcavitiesaredeterminedbyphysicaladsor

16、ption.N2,ArorO2wasalwaysusedasadsorbatesothatwecanmeasureporevolume,specificsurfacearea,poresizedistributionofporousmaterial.microporousmaterialsultraporousmaterialsmesoporousmaterialsmacroporousmaterialtypeIVtypeIItypeItypeVI相对庄力-AdsorptionequilibriumisothermClassificationofadsorptionisothermsbyIUP

17、ACHysteresisIftheadsorption-desorptionisnotcompletelyreversible,theadsorption-desorptionisothermsarcnotcoincident.ThisphenomenonmainlyoccurredintypeIVadsorptionequilibriumisotherm.相対ii力FourkindsofhysteresisloopHl:Thehysteresisloopisverysteepandalmostparallel.Mainlyformedbyuniformsizeandshapehole.H2:

18、Theadsorptionbranchoftheadsorptionisothermisgraduallyincreasingduetothephenomenonofcapillarycondensation,thedesorptionbranchessuddenlyfellunderarelativelylowrelativepressureatthesametime.Desorptionissuddenlyhappenedinadsorbates,FourkindsofhysteresisloopH3&H4:Mainlyattributedtoslitchannel.WCapillaryc

19、ondensationofcylindricalporesAdsorptionDesorptionElectronmicroscopictechniqueOpticalmicroscope:ThemagnificationofopticalmicroscopyisseveralthousandtimesBecauseofthelimitationoflightwave,itsresolutionisnotlessthan0.2pm.Electronmicroscope:Magnificationoftheelectronmicroscopecanreachamillion.The。smalle

20、stdetailscanberesolvedareseveralA.ScanningelectronmicroscopeTheprincipleofSEMisthattheelectroniclineisilluminatedinthesample,andthesignaliscollectedfromthesurfaceofthebulksample.SEMcanaccuratelyreflectthemorphologyofthesurfaceofthespecimenImagehasathree-dimensionalsense.ScanningelectronmicroscopeObs

21、ervethestructureofthesurfaceofthesampledirectly.Thesizeofsamplecanbelargeas120mmx80mmx50mm.Samplepreparationprocessissimple,neednotcutintothinslicesSamplecanbeusedforthreedegreesofspaceinthesampleroomfortranslationandrotationsothatwecanobservethesamplefromvariousangles.Depthoffieldislarge.Imagehasat

22、hree-dimensionalsenseScanningelectronmicroscopeTheimageofawiderangeofmagnification,resolutionisrelativelyhigh.ItcanexpandtoadozentimestohundredsofthousandsoftimesResolutionisbetweenopticalmicroscopeandtransmissionelectronmicroscope,about3nm.Electronbeamcanlittledamageandcontaminationthesample.During

23、theobservationofmorphology,itcanalsobeusedtoanalyzetheothersignalsfromthesampletomakethemicroareacompositionanalysis.TransmissionelectronmicroscopeTEMincludeslightingsystem,imagingsystem,andobservation-photostudio.TEMcanclearlydisplaythelocalstructureofthecrystal.Theporestructureofmolecularsievecanb

24、eobserveddirectly.TEMwasusedtoobservethemorphology,size,particlesize,particlesizedistributionofthepowderandsoon.Transmissionelectronmicroscopea.ElectrondiffractionanalysisbConvergentbeamelectrondiffractionanalysisc.TransmissionelectronimageanalysisdHighresolutionimageanalysisScanningandenergyspectru

25、manalysissystemMicrodiffractionandmicrodiffractionanalysisOthermethodsofelectronmicroscopyr1L1:EIV1Jr1FIIV1Jr1L.EEC)J1BEknilectrciprobBr1E:SC/JAESNuclearmagneticresonanceAtoolforqualitativeanalysisofthecompositionandstructureoforganicmatterandinorganicmatte匚Aneffectivemethodtoanalyzeandidentifythemi

26、croporousandmesoporousmaterials.Bytheapplicationoftechnologieslikecrosspalarization,magicanglespinning,totalsidebandsuppressionanddipolardiphasing,quantitativefunctioncanberealizedInfraredspectrumInfraredspectrumcanbeusedtocharacterizethechemicalbondsandtocharacterizethemolecularstructure.Infraredsp

27、ectrumhastheadvantagesoflesssample,simplesampleprocessing,quickmeasurement,convenientoperationandsoon.ApplicationinMolecularsieve：IdentificationofmolecularsieveframeworkCompositionanalysisofframeelementsCationdistributionSurfacehydroxylstructureSurfaceacidityCatalyticperformanceObjectstructureofmole

28、cularsieveThermalanalysisThermalanalysisisthestudyofmaterialintheprocessofheatingorcoolingThisanalysishavetheadvantagesofsensitive,fastandaccurateThemostofapplicationsarethecombinationofTGAandDTATheapplicationofthermalanalysistechniqueinmolecularsieveanalysisincludesdeterminationofthecontentofmolecu

29、larsieve,thecontentoforganictemplate,thermalstability,desorptionmechanismandsoon.Thermalanalysistechniquer1TGA|DGADSCAmethodfor1TomeasureWhentheanalyzingthe1thedifferentmeasuredmaterialweightchangeof1temperatureabsorbsorreleasesthesampleinthe1riseoftheheat,reduceorheatingprocess1measuredincreasetheb

30、ymeasuringthe1objectandthequantityofheattoweightofthe1referencethesample.Recordsample.Ji1LmaterialjtheheatchangeChemicalcompositionandmacroscopicpropertiesICP:ICPhasthecharacteristicsofhighprecision,lowmatrixinterference,andwiderangeofcalibrationcurveItiswidelyusedinthequalitativeandquantitativeanal

31、ysisofinorganicelements11iswidelyusedinthequalitativeandquantitativeanalysisofinorganicelements.AAS:Thecharacteristicsofhighsensitivity,goodselectivity,anddeterminationofelementsXRF:Theatomisexcitedbyhighenergyradiation,anditsinnerelectronleveltransition,emittingcharacteristicXray.Itcanmeasuresomeno

32、nmetalandmakethesamplesimpleMethodsHydrothermalsynthesisMolecularsieveisakindofcompoundswithmicroporousskeletalstructurebyburningorchemicaltreatment,extraction,microwave,removingtemplateagentetc;orthroughtheprocessofbackbonemodification,ionexchange,isomorphousreplacementwiththesurfaceandporemodifica

33、tionsecondarysynthesismethodtoobtainaspecificporestructureandpropertiesofmaterialHydrothermalandsolventthermalsynthesisisthemethodofasolventinacertaintemperature(100-1000C)andpressure(1-1OOMPa)conditionsoccurringaspecificchemicalreactionSyntheticreactionsaregenerallyperformedinaparticulartypeofclose

34、dvesselorautoclaveThereactionisinsubcriticalandsupercriticalconditionsTwomainfeatures1Theresearchsystemisinnonidealandnonequilibriumstatesothatwecanusenonequilibriumthermodynamicstosolvethesynthesisofchemicalproblems.2.HydrothermalandsolventthermalchemicalpropertiesareoperableandvariableFivemainfunc

35、tionsDuetothechangeofthereactionpropertiesofthereactantsandtheincreaseoftheactivityandtheeffectoftheproduct.Hydrothermalandsolventthermalmethodsmaybeusedinthechemicalreactions,whicharedifficulttobeusedinthesynthesisofsolidstatereaction.Thespecialredoxintermediatestate,metastablephaseandsomespecialph

36、asecanbeeasilygeneratedinthehydrothermalandsolventthermalconditionsItcanmakethesubstancewhichhaslowmeltingpoint,highvaporpressureandcannotbegeneratedinthemeltaswellashightemperaturedecompositionphasecrystallizeinthehydrothermalandsolventunderlowtemperatureconditions.FivemainfunctionsThereactioncondi

37、tionslikelowtemperature,pressureandliquidphaseofhydrothermalandsolvothermalarefavorabletothegrowthofthelessdefects,thecontrolorientation,theperfectcrystalandeasytocontrolthesizeandmorphologyproductsDuetotheeaseoftheenvironmentalatmosphereandregulatingtheoxidationandreductionpotentialofrelatedmateria

38、lsinthehydrothermalandsolventthermalconditions,theformationofsomespeciallowvalencestate,intermediatevaleneestateandspecialvalencecompoundcanbeeasilycompleted,andcanbeuniformlydoped.Basictypesa)Syntheticreactiong)IonexchangereactionCrystallizationreactionHydrolysisreactionSinglecrystalcultivationHeat

39、treatmentreactionTransferreactionShrinkagereactionExtractionreactionOxidationreductionreactionPrecipitationreactionSinteringreactionm)HydrothermalhotpressingreactionbHydrothermalsynthesistechniqueReactionvessel,reactioncontrolsystem,waterandsolventthermalsynthesisprogramandin-situcharacterizationtec

40、hnique.SyntheticrouteRoute:GenerationofhydratedgelandcrystallizationofhydratedgelCrystallizationTheaggregationofmultiplesilicateandaluminateNucleationofmolecularsievesNucleargrowthGrowthofmolecularsieveandtwonucleationReactantSiliconsource,aluminumsource,metalion,alkali,othermineralagent,water.Silic

41、onsource:Na2OxSiO29Na2SiO3-9H2O,silicagel,fumedsilica,TEOS,TMeOSAluminumsource:NaAlO2,A1OOH,A1(OH3),Al(i-OC3H7)3,A1(NO3)3-9H2O,metalaluminumSilica-AluminaratioThestructureandcompositionofthefinalproductinthereactionmaterialsareimportanttothefinalproduct.Inmostcases,molecularsievesoflowsilicon-alumin

42、umratiolikeLTA,SOD,KH,KJ,etc.havebeencrystallizedbyhighpHvalue,lowsilicon-aluminuminitialmaterials.HighsilicamolecularsievelikeMOR,BEAhavebeencrystallizedbylowpHvalue,highsilicon-aluminuminitialmaterials.Alkalinity/Thesynthesisofmolecularsievesiscarriedoutundertheconditionofalkaline.Improvingthealka

43、linityofthesyntheticsystemcanconducivetotheformationofrichaluminummolecularsieve./Whentheconcentrationofalkaliconcentrationincreases,theproductsizebecomessmallerandthesizedistributionbecomesnarrow.AgeingMixtheinitialmaterialuntilthebeginningofcrystallization.ThisperiodiscalledageingThemainexistencei

44、nthesynthesissystemissilica-aluminagelandcorrespondinggelliquidphase.Controlthereactionconditionsliketemperatureandtimeareadvantagetothetransformationandnucleationofgels.CrystallizationandageingtemperatureThetemperaturechangeofcrystallizationandageingreactioncantriggerthetransformationofthepolymeriz

45、ingconditions,polymerization,gelformationanddissolutioninsiliconionsandaluminiumionsandpolymerizationofgelsandgelsbetweenliquid.SecondarysynthesismethodsTemplateremovalHydrothermalsynthesismethodcanbeusedtosynthesisaspecificbackbone,componentelementsandthestructureofthemolecularsieve.Inadditiontopar

46、tofthezeolites,mostofthebackbonesofthemolecularsievecontainorganicmoleculesusedasstructuredirectingagent.ThreemainmethodsHightemperaturecombustionmethodChemicalreactionmethodSolventextractionmethodSecondarysynthesis:ModificationandfurtherprocessingofmolecularsievestructurePropertiesandfunctionsofmol

47、ecularsievedependsonitsbackbonestructureandcounterions.CationexchangeReactioncanbeexpressedas十沁ZA,ZBisvalencestatechargeofexchangeablecationAandB.(M),(S)iszeolitefaciesandsolutionfaciesrespectively.AluminumremovalDealuminzationultrastabilizationthroughthermaltreatmentandhydrothermaltreatmentrouteChe

48、micaldehydrationrouteSiCl4routeisthemostfamiliar.Optimizationgroupingofthermaltreatmentandchemicaldehydration.PoreandsurfacemodificationCationexchangemethodChannelmodificationOutersurfacemodificationUASyntheticmethodDissolve0.723gNaOHinto80mLdeionizedwater,stirringfor10-20min,mixinguntilfulldissolution.Dividethesolutionintotwoparts,placedintwopolypropylenebottlesAdd8.258gNa2Al2O4intooneoftheNaOHsolutions(a),stirringfor10-20minuntilfulldissolution.Coverthebottleuntilclarification.Add15.48gNa2SiO3intoanotherNaOHsolution(b),stirringfor10