简介：ThecatalyticactivityofFe/ZSM-5fortheselectivereductionofNOtoN2withmethaneinthepresenceofexcessO2wasstudied.Fe/ZSM-5catalystswithvariousFeloadingswerepreparedbyimpregnationmethod.ItiswellknownthatmethaneisinactivewhenFe/ZSM-5asthecatalystfortheselectivecatalyticreduction(SCR)ofNOwithmethane.However,thispapershowsthatwhenthecontentofFewasabout0.5%,Fe/ZSM-5showedhighercatalyticactivityandselectivityofmethane,andputforwardmeasurableactivationforCH4isanimportantfactorforthereactionofremovalofNOxwithCH4.

简介：TheinfluenceofmischmetaladditiononphysicochemicalpropertiesofPtSnNa/ZSM-5catalystwasstudiedbymeansofXRF,H2chemisorption,XRD,TPR,NH3-TPDandTPOtechniques.TheresultsshowedthatthepresenceofmischmetalhadanobviousimpactonthecatalyticperformanceofthePtSnNa/ZSM-5catalyst.AsuitablecontentofmischmetalnotonlycouldenhancetheinteractionsbetweenPtspeciesandthesupport,butalsoinhibittheformationofcokeduringthereaction,thusimprovingthecatalyticactivityandstability.Inourexperiments,whenthecontentofmischmetalwas3m%,thecatalystexhibitedbestcatalyticperformance.However,thecontinuousadditionofmischmetalcouldpromotethereductionofSnspeciestometallictin,whichwasdisadvantageoustothereaction.

简介：教主的联盟者组织了ZSM-5独块巨石通过转变宏的骨骼被准备多孔的硅石胶化进由帮助蒸气的conversionmethod.The形态学和宏的整体的形状的ZSM-5多孔的硅石胶化preserved.Thehierarchically很好被组织ZSM-5独块巨石展出了层次孔，与在宏内存在的中央毛孔andmacropores多孔的硅石胶化，并且ZSM-5.Theproducts形成的微毛孔被使用XRD，SEM和N_2adsorption-desorptionmethods适当地描绘了。

简介：AseriesofZSM-5zeolites,withthemorphologiesofsphere,spherewithcubicparticlesonthesurface,andcubicparticles,weresynthesizedbyhydrothermalmethodusingn-butylamineasthetemplate,assistedbytheadditionofNaClandcrystalseed.X-raydiffraction(XRD),scanningelectronmicroscope(SEM),X-rayfluorescence(XRF)andtemperature-programmeddesorptionofammonia(NH3-TPD)wereusedtocharacterizethesesamples.Thesamplesweretestedwithtoluenemethylationreaction.Themodifiedsamplecomposedofsphericalparticleswith3μmcrystalparticlesonthesurfacehadapara-xyleneselectivityof95%andmaintained79%oftheinitialconversionafterrunningthereactionfor50h.Thismodifiedsampleshowedthebeststabilityamongthetestedthreemodifiedsamples.

简介：CarbondepositionduringmethanoltohydrocarbonsleadstothequickdeactivationofZSM-5catalystanditisoneofthemajorproblemsforthistechnology.DecreasingthecrystalsizeorintroducingmesoporesintoZSM-5zeolitescanimproveitsdiffusionpropertyanddecreasethecokeformation.Inthispaper,nano-sizedZSM-5zeolitewithintercrystallinemesoporescombiningthemesoporousandnanosizedstructurewasfabricated.Forcomparison,themesoporousZSM-5andnano-sizedZSM-5werealsoprepared.ThesecatalystsampleswerecharacterizedbyXRD,BET,NH3-TPD,TEM,Py-IRandTGtechniquesandusedontheconversionofmethanoltogasolineinafixed-bedreactoratT=405°C,WHSV=4.74h-1andP=1.0MPa.Itwasfoundthattheexternalsurfaceareaofthenano-sizedZSM-5zeolitewithintercrystallinemesoporesreached104m2/g,largerthanthatofmesoporousZSM-5(66m2/g)andnanosizedZSM-5(76m2/g).Catalyticlifetimeofthenano-sizedZSM-5zeolitewithintercrystallinemesoporeswas93h,whichwasonlylongerthanthatofmesoporousZSM-5(86h),butshorterthanthatofnanosizedZSM-5(104h).Strongaciditypromotedthecokeformationandthusdecreasedthecatalyticlifetimeofthenano-sizedZSM-5zeolitewithintercrystallinemesoporesthoughitpresentedlargeexternalsurfacethatcouldimprovethediffusionproperty.Thespecialzeolitecatalystwasfurtherdealuminatedtodecreasethestrongacidity.Afterthis,itscokeformationratewasslowedandcatalyticlifetimewasprolongedto106hbecauseofthelargeexternalsurfaceareaanddecreasedweakacidity.Thisspecialstructuralzeoliteisapotentialcatalystformethanoltogasolinereaction.

简介：FreshZSM-5zeolitecatalystswerepretreatedat460℃and500℃withvariouscumulativeamountofwaterfeed(CAWF)inafixedbedreactor.Thecatalyticprocesswascarriedoutunderthefollowingconditions:atemperatureof480℃;amethanolWHSVof3h-1;amethanolpartialpressureof30kPa;andatimeonstreamof12h,24hand48h,respectively.TheBETparametersofcatalystsanddiffusioncoefficientsoftolueneshowedthatthereweretwotypesofmesoporesgeneratedunderdifferenthydrothermalconditions.MildtemperatureandmoderateCAWFconditionsledtoexternalopenmesoporeswhichcouldbeenteredfromtheexternalsurfaceofthezeolite,whileahightemperatureorahighCAWFconditionresultedinthegenerationofmacroporesorinternalisolatedmesopores,whichwereoccludedinthemicroporousmatrix.TheTGAresultsshowedthatcatalystwithexternalopenmesoporeshadgoodabilitytoresistcokeaccumulationandgoodperformanceonpropyleneselectivity,whiletheinternalisolatedmesoporesdidnocontributetotheincreaseddiffusivityofreactantsandproducts.

简介：摘要：使用NH4Cl溶液对以四乙基溴化铵为模板剂合成ZSM-5工业原粉分别进行焙烧前后的铵交换实验，采用火焰光度法测量铵交换前后Na2O含量并计算出交换度，考察焙烧前后对分子筛铵交换效果的影响，并分析出现交换度差异的原因。

简介：<正>ZSM-5/MCM-41compositemolecularsievewaspreparedbythenano-assemblingmethod.TheZSM-5molecularsieve,theMCM-41molecularsieve,theZSM-5/MCM-41mechanicalmixtureandtheZSM-5/MCM-41compositemolecularsievewerecharacterizedbyX-raypowderdiffractometry,N2adsorptionisotherms,temperatureprogrammeddesorptionofammoniaandscanningelectronmicroscopyandtheirpropertieswereanalyzed.UsingFCCgasolineasthefeed,activitiesofdifferentmolecularsievesforreducingolefincontentwereinvestigatedinacontinuoushigh-pressuremicro-reactorunitunderthefollowingconditions:areactiontemperatureof400℃,areactiontimeof2h,aweighthourlyspacevelocityof3h-1,andareactionpressureof2.0MPa.TheresultsshowedthattheHMCM-41molecularsievehadlowreactionperformance,andtheHZSM-5molecularsievedemonstratedhigharomatizationactivity,whiletheZSM-5/MCM-41compositemolecularsieveexhibitedabestolefin-reducingperformancebecauseofitshighisomerizationactivityandmoderatearomatizationactivity.Withalargestolefin-reducmgcapabilityandareasonabledistributionofproducts,thecompositemolecularsievewasmoresuitableforFCCgasolineupgradingcomparedtootherthreecatalysts.

简介：

简介：NanosizedGa-containingZSM-5zeoliteswerepreparedviaisomorphoussubstitutionandimpregnationfollowedbycharacterizedusingvarioustechniques.Thecatalyticperformanceofthezeolitesforthearomatizationof1-hexenewasinvestigated.TheresultsindicatethatisomorphoussubstitutionpromotestheincorporationofGaheteroatomsintotheframeworkalongwiththeformationofextra-frameworkGaO+species（[GaO+]a）thathavestrongerinteractionswiththenegativepotentialoftheframework.Inaddition,basedonthePy-IRresultsandcatalyticperformance,the[GaO+]aspecieswithstrongerLewisacidsitesproducedabettersynergismwithmoderateBr?nstedacidsitesandthusimprovedtheselectivitytoaromaticcompounds.However,theimpregnationresultsintheformationofGa2O3phaseandsmallamountsofGaO+speciesthataremainlylocatedontheexternalsurface（[GaO+]b）,whichcontributetoweakerLewisacidsitesduetoweakerinteractionswiththezeoliteframework.During1-hexenearomatization,thenanosizedGaisomorphouslysubstitutedZSM-5zeolitesamples（Gax-NZ5）exhibitedbettercatalyticperformancecomparedtotheimpregnatedsamples,andthehighestaromaticyield（i.e.,65.4wt%）wasachievedovertheGa4.2-NZ5sample,whichcontainedwiththehighestGacontent.

简介：摘要：ZSM-5择形分子筛作为FCC催化剂中的关键材料，因其特殊的孔结构和酸度，可有效增加丙烯收率、提高汽油高辛烷值。使用改性择形分子筛制备的助剂稳定性显著提高，并且可显著提高低碳烯烃的选择性。本文制备了不同磷酸盐改性的ZSM-5，根据制备过程中各个环节的实验数据得出了三种磷酸盐所适合的催化剂制备方法。

简介：利用Gaussian03计算软件包,在DFT-B3LYP/3-21G水平上对ZSM-5分子筛128T簇模型进行了研究.通过分析T—O—T基团键角、桥羟基键长、质子电荷和分子轨道能隙等数据,讨论了ZSM-5分子筛硅铝比与其Brnsted酸性的关系,预测了其催化性能.计算结果表明,ZSM-5分子筛硅铝比越低,酸性越强,相应的催化性能越好,与实验结果相符.

简介：摘要：通常情况下SOF2水解反应速率较低，在利用SOF2水解反应检测SOF2的技术实用化过程中就需要较大的反应器，而且检测时间较长。为了提高SOF2水解反应速率，本文研制了Pt/ZSM-5催化剂催化SOF2的水解反应，可得到反应最优条件为：当Pt负载量为2.29%、温度为393K、催化剂Pt/ZSM-5使用量为0.53g时，水解速率常数最大为10.49×10-4s-1。该催化剂能使SOF2在200min内完全水解为SO2。

简介：摘要：ZSM-5分子筛在催化裂化催化剂制备过程中作为活性组分，其粒度分布状况的优劣对于催化剂产品的强度、活性、稳定性等性能的影响至关重要。将卧式砂磨技术应用于ZSM-5分子筛制备工艺，使分子筛的粒度分布更加优化，使分子筛制备过程更加高效、节能、环保、可操作性强。

简介：Micro-mesoporouscompositemolecularsievesH-ZSM-5/MCM-41werepreparedbythehydrothermaltechniquewithalkali-treatedH-ZSM-5zeoliteasthesourceandcharacterizedbyscanningelectronmicroscopy,transmissionelectronmicroscopy,energydispersivespectroscopy,X-raydiffraction,N2adsorption-desorptionmeasurementandNH3temperature-programmeddesorption.ThecatalyticperformancesforthemethanoldehydrationtodimethyletheroverH-ZSM-5/MCM-41wereevaluated.Amongthesecatalysts,H-ZSM-5/MCM-41preparedwithNaOHdosage(nNa/nSi)varyingfrom0.4to0.47presentedexcellentcatalyticactivitywithmorethan80%methanolconversionand100%dimethyletherselectivityinawidetemperaturerangeof170—300℃,andH-ZSM-5/MCM-41preparedwithnNa/nSi=0.47showedconstantmethanolconversionofabout88.7%,100%dimethyletherselectivityandexcellentlifetimeat220℃.Theexcellentcatalyticperformanceswereduetothehighlyactiveanduniformacidicsitesandthehierarchicalporosityinthemicro-mesoporouscompositemolecularsieves.ThecatalyticmechanismofH-ZSM-5/MCM-41forthemethanoldehydrationtodimethyletherprocesswasalsodiscussed.

简介：综述了近年来ZSM-5沸石分子筛的合成及表面改性研究进展.合成方面重点介绍了有机胺合成、无机胺合成及负载合成方法;表面改性方面重点介绍了水蒸气改性、离子交换改性及化学气相沉积改性方法.

简介：Inthisworktypicalmechanicalpropertiesforacatalystsupportmaterial,ZSM5(aspray-driedgranularzeolite),havebeenmeasuredinordertorelatethebulkbehaviourofthepowdermaterialtothesingleparticlemechanicalproperties.Particleshapeandsizedistributionofthepowders,determinedbylaserdiffractionandscanningelectronmicroscopy(SEM),confirmedthesphericalshapeofthespray-driedparticles.TheexcellentflowabilityofthematerialwasassessedbytypicalmethodssuchastheHausnerratioandtheCarrindex.Thiswasconfirmedbybulkmeasurementsoftheparticle-particleinternalfrictionparameterandflowfunctionusingaSchulzeshearcell,whichalsoillustratedthelowcompressibilityofthematerial.SingleparticlecompressionwasusedtocharacterizesingleparticlemechanicalpropertiessuchasreducedelasticmodulusandstrengthfromHertzcontactmechanicstheory.Comparisonwithsurfacepropertiesobtainedfromnanoindentationsuggestsheterogeneity,thesurfacebeingharderthanthecore.Inordertoevaluatetherelationshipbetweensingleparticlemechanicalpropertiesandbulkcompressionbehaviour,uniaxialconfinedcompressionwascarriedout.ItwasdeterminedthattheAdamsmodelwassuitablefordescribingthebulkcompressionandfurthermorethattheAdamsmodelparameter,apparentstrengthofsingleparticles,wasingoodagreementwiththesingleparticlestrengthdeterminedfromsingleparticlecompressiontest.

简介：TheepoxidationofallylchloridewithH2O2onTi-ZSM-5preparedbyisomorphoussubstitutionofHZSM-5withTiCl4gaswasstudied.TheresultsshowthatTi-ZSM-5hasahighcatalyticefficiencyfortheepoxidationofallylchloride.TheH2O2utilizationreaches99.50%whentheallylchloride/H2O2molarratiois>1.Theeffectofsolventspecies,catalystconcentration,H2O2andallylchlorideconcentrationandreactiontemperatureontheepoxidationwasinvestigatedsimultaneously.Itisfoundthatmethanolisthebestsolventforthereaction.Thereactionrateequationwithv=k[Cat.][H2O2]1/2-[C3H5Cl]andtheapparentactivationenergywithEa=63.462kJ/molareobtainedaccordingtothekineticsstudy.

简介：碱性体系中以水玻璃和硅溶胶为双硅源，硫酸铝为铝源，在硅铝酸盐凝胶形成过程中加入氧氯化锆，用水热晶化法成功合成了Zr-ZSM-5分子筛。通过XRD、Raman、UV-VIS、BET、SEM、NH3-TPD、Py-IR等手段对其进行表征。研究结果表明：Zr成功进入ZSM-5分子筛骨架，且随着锆摩尔含量的增加，分子筛的比表面积减小，孔径和孔体积增大，势必会影响到分子筛的择形催化性能；此外，分子筛的酸类型重新分布，L酸比例增大，总酸量和酸强度有所减小，势必会影响其酸催化性能；同时分子筛的生长方式也发生了改变，晶体结构由三维棺状变为二维层片状，相对结晶度有所降低，但其骨架结构依然保持完整。

简介：试验制备了Pd/CeO2-ZSM-5/CC催化剂,测定了其对低中温尾气CO的催化净化活性。试验表明,Pd/CeO2-ZSM-5/CC催化剂具有良好的催化活性,Pd负载量大的催化剂活性越好。CO初始浓度为100ppm,O2浓度为21%,空速为100000h-1时,0.4%Pd催化剂的T100为192℃。