题目硅源量和晶化时间对ZSM-5分子筛结构和性能的影响TITLEEffectofsiliconsourceandcrystallizationtimeonstructureandpropertiesofZSM-5zeolites摘要芳烃是一种重要的有机化工产品，其中苯、甲苯和二甲苯是生产精细化学品的主要原料。随着芳烃日益增加的市场需求以及煤、石油和天然气资源的逐年减少，芳烃产品的年产量已经不能满足当今社会的需求。而CH3OH制芳烃(MTA)的工艺不但可以把产量过剩的CH3OH充分利用，而且可以用CH3OH为原料制得不含硫、磷等对环境有害的元素的芳烃产品，是一种绿色高效的芳烃生产工艺[1]。所以，用来催化MTA反应的ZSM-5分子筛催化剂已经成为开发MTA技术的关键。本文针对在MTA反应中ZSM-5分子筛容易失活且产品中的芳烃选择性较低的状况，通过Ｘ射线衍射、扫描电镜和比表面积测试的表征手段，考察了分子筛的硅源种类以及用量、晶化时间长短对提高ZSM-5分子筛的活性和BTX芳烃的选择性的影响。实验结论如下：由于硅溶胶生产原理简单，含硅量高，利于工业放大生产，所以选取硅溶胶作为硅源。在硅源量为x=0.6（即硅铝比为0.6）时，合成的ZSM-5分子纯度最佳，杂晶最少。当晶化时间为48h时，合成的ZSM-5分子筛相对结晶度达到100％，此时其表面积达到最大值525m2g-1。此时合成的ZSM-5分子筛的芳烃收率为81.94％，并且其在CH3OH制芳烃反应中催化性能最佳。在上述条件下所合成的ZSM-5分子筛对邻二甲苯的选择性最高，其转化结果是45.32％。关键词：ZSM-5；分子筛；微介孔；MTA；芳构化AbstractAromatichydrocarbonisanimportantorganicchemicalproduct.Benzene,tolueneandxylenearethemainrawmaterialsforproducingfinechemicals.WiththeincreasingmarketIdemandofaromaticsandthedecreasingofcoal,oilandnaturalgasresourcesyearbyyear,theannualoutputofaromaticsproductscannotmeettheneedsoftoday'ssociety.Theprocessofcatalyticconversionofmethanoltoaromatics(MTA)cannotonlymakefulluseoftheexcessmethanol,butthearomaticsproducedbymethanolasrawmaterialshavenoharmfulenvironmentalelementssuchasphosphorusandsulfur,whichisahighlyefficientaromaticsproductionprocess.Therefore,theZSM-5zeolitecatalystusedtocatalyzetheMTAreactionhasbecomethekeytodevelopingMTAtechnology.Inthispaper,ZSM-5molecularsievesareeasilydeactivatedinMTAreactionandtheselectivityofaromatichydrocarbonsinproductsislow.Theeffectsofsiliconsource,amountandcrystallizationtimeofmolecularsievesontheactivityofZSM-5molecularsievesandtheselectivityofBTXaromaticsareinvestigatedbymeansofXRD,SEMandBET.Theexperimentalconclusionsareasfollows:Becausesilicasolhassimpleproductionprincipleandhighsiliconcontent,itisconducivetoindustrialscaleproduction.Silicasolisselectedassiliconsource.Whenthesiliconsourceisx=0.6(i.e.siliconaluminumratiois0.6),thepurityoftheZSM-5moleculeisthebestandtheimpurityistheleast.Whenthecrystallizationtimeis48h,therelativecrystallinityofthesynthesizedZSM-5zeolitereaches100%,andthesurfaceareareachesthemaximumvalueof525m2g-1.ThearomaticsyieldofthesynthesizedZSM-5zeoliteis81.94%,andithasthebestcatalyticperformanceinthereactionofmethanoltoaromatics.TheZSM-5zeolitesynthesizedundertheaboveconditionshasthehighestselectivityforo-xylene,andtheconversionresultis45.32%.Keywords:ZSM-5;Molecularsieve;Mesoporous;MTA;AromatizationII目录1文献综述....................................................................11.1CH3OH制芳烃（MTA）工艺...................................................11.1.1CH3OH的应用及生产工艺................................................11.1.2芳烃的来源和应用.....................................................21.1.3CH3OH制芳烃研究背景..................................................31.1.4MTA工艺的催化剂.................
