均相和非均相催化剂-英文PPT.ppt 14页

readingrepresentationCATALYST catalyst"sconsiderationactivity,selectivity,efficiencyseperationofproduct,reactantandcatalystmechanicalbehaviourenvironmentalperformancefeatureofacatalyst classificationhomogeneouscatalystheterogeneouscatalyst homogeneouscatalystadvantage:highactivityandselectivity-promotereactionfrommolecularsizedrawback:diffculttorecyclecatalystandseperateproduct-catalyst,productandreagentallinonephasehomogeneouscatalysteg.metal-organiccomplex,salt hetergeneouscatalystadvantage:easytoseperate-catalyst,productandreagentindifferentphasesdrawback:lowactivityandselectivity-promotereactionmainlyfromphaseinterfacehetergeneouscatalysteg.metal,metaloxide howtocombineadvantages1.distributecatalyst,productsandreagentsintodifferentphases-L-L,L-L-Ssystemsandsoon2.immobilizationofhomogeneouscatalyst-findapropercatalystsupport3.supportedliquid-phasecatalyst-findasupportandaliquidfilm back-mixingengineeringfactorsback-mixingisbeneficialtoreactionsystemback-mixingisunfavorabletoreactionsystemback-mixingisalwayscausedbystirringwhichproducesashearingforcefield back-mixingisneededtoL-Lsystemshearingforcefieldmaybreakliquidintodroplet,increasestwophase"scontactingareatoSL-PCusefulshearingforcefieldwilldestroyliquidfilm"sstabilityharmfulashearingforceexists back-mixingisneedlesstoL-Lsystemtwophase"scontactingareawillbeverylimitedtoSL-PCharmfulliquidfilm"sstabilitywillelevateandcatalystcouldbeusedinaPFRusefulashearingforcedisappears SL-PC"sstructuresupport(inertia,specificsurface,aperture)liquidfilm(moistening,non-volatile,solubility,stability)activeconstituent(dependonreaction)preparationofSL-PCscoutforproperstuffeg.Renay-nickel,Al2O3,controlledporeglass,polystyreneeg.highboilingpointorganicsolvent,water,moltensalt L-Lsystemliquid1liquid2preparationofL-Lscoutforproperliquidgoodsolventforreagentsandproduct,oronlyoneofthemgoodsolventforonlycatalystfeaturesincommen:environmental,non-volatile,economic,selectivityandsoon agoodcatalysthighactivity,selectivity,efficiencyeasyseperationofproduct,reactantandcatalystenoughmechanicalbehaviourexcellentenvironmentalperformanceevaluationofacatalystntuitionisticcriterion:conversion,seclectivity,reactionrate,yieldcoefficient SL-PCcontrolmeasuresengineeringfactor:particalsize,spacevelocityintrisicfactor:differentsupport,liquidfilmandpreparationmethodsL-Lengineeringfactor:amountoftwophases,spacevelocityintrisicfactor:differentliquid Thanks!