负载型TS-2分子筛的制备及其性能初步研究.docx

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摘要

钛硅分子筛是指将过渡金属钛引入全硅分子筛骨架，钛元素的成功引入使分子筛具有活化双氧水的能力，因而具有了优异的催化性能。使用过氧化氢和钛硅分子筛的催化体系在苯酚羟基化生产苯二酚时，可以降低反应条件，简化工艺流程，且环境友好，是世界上公认的最有价值和发展前途的生产工艺。

本文采用二次水热生长法在α-Al2O3陶瓷微球表面成功制备了TS-2分子筛层，并利用SEM、FT-IR、XRD、UV-Vis等方法对其结构进行表征。发现纳米级胡桃状负载型TS-2分子筛能致密负载在α-Al2O3微球表面，TS-2分子筛的粒径大小为300-600nm，钛主要以四配位钛形式存在。在苯酚羟基化反应体系中加入制备的负载型TS-2分子筛，分子筛表现出较强的催化性能，当反应温度为65oC，双氧水总量和苯酚的摩尔比为2:1时，苯酚转化率能达到38.84%，苯二酚的选择性达到96.8%。

关键词：负载型TS-2分子筛；二次水热生长法；微球载体；苯酚羟基化

Abstract

Titaniumsilicalitesreferstotheintroductionoftransitionmetaltitaniumintotheallsiliconzeoliteframework,thesuccessfulintroductionoftitaniumelementmakesthezeolitehastheabilitytoactivatehydrogenperoxide,andthushasexcellentcatalyticperformance.Thecatalyticsystemusinghydrogenperoxideandtitaniumsilicalitesinthephenolhydroxylationproductionofp-benzoquinonecanreducereactionconditions,simplifytheprocessflow,andisenvironmentallyfriendlyandrecognizedgloballyasthemostvaluableandpromisingproductionprocess.

Inthisstudy,supportedTS-2zeolitewassuccessfullysynthesizedonthesurfaceofα-Al2O3ceramicmicrospheresusingthesecondaryhydrothermalsynthesismethod.Inaddition,thestructurewascharacterizedusingtechniquesincludingSEM,FT-IR,XRD,UV-Vis.Itwasfoundthatadenselayerofnanowalnut-shapedSupportedTS-2zeolitewithaparticlesizeof300-600nmcouldbeloadedonthesurfaceofα-Al2O3microspheres,andthetitaniumspeciespresentweremainlytetracoordinatedtitanium.ThepreparedsupportedTS-2zeolitewasappliedtothephenolhydroxylationreactionsystemandshowedstrongcatalyticperformance.Atareactiontemperatureof65°Candwithamolarratiooftotalhydrogenperoxidetophenolof2:1,thephenolconversionratecanreach38.84%,andtheselectivityofcatecholcanreach96.8%.

Keywords:SupportedTS-2zeolites;Secondaryhydrothermalgrowthmethod;microspherecarrier;Phonelhydroxylation.

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目录

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