水热法合成13X型沸石的相变转化机理  

Phase transformation mechanism of Zeolite 13X synthesized by hydrothermal method

作　　者：黄志良[1] 石月[1] 鲁冕[1] 李伟[1] 詹刚[1] 陈巧巧[1] 杨秀[1] 池汝安[2] 

机构地区：[1]武汉工程大学材料科学与工程学院,湖北武汉430074 [2]武汉工程大学化工与制药学院,湖北武汉430074

出　　处：《武汉工程大学学报》2012年第12期32-37,共6页Journal of Wuhan Institute of Technology

基　　金：湖北省自然科学重点基金(No.2011CDA050);国家973预研项目(No.2011CB411901);教育部长江学者与创新团队项目(No.IRT974)

摘　　要：以偏铝酸钠、九水硅酸钠、氢氧化钠和蒸馏水为原料,采用水热法合成13X沸石,为探究其相变转化机理,通过X射线衍射(XRD)、扫描电子显微镜(SEM)、红外(FT-IR)光谱分析和拉曼(Raman)光谱分析等测试手段,对不同反应时间合成的样品进行了物相、显微形貌及骨架结构演变的分析.结果表明,13X型沸石的硅铝酸阴离子骨架在反应初期就已形成,其晶化过程是不同类型13X沸石的物相演化过程,对应于沸石骨架中硅铝原子比的不断修正.随着沸石骨架中硅铝原子比先减小后增大,13X沸石的相变过程经历了一个先正相变后逆相变的过程,总相变式为:13X型沸石(Ⅰ)(Na1.84[(Al2Si4)O11.92]·7H2O)→13X型沸石(Ⅱ)(Na2[Al2Si3.3O10.6]·7H2O)和13X型沸石(Ⅲ)(Na2.06Al2Si3.8O11.63·8H2O)→13X型沸石(Ⅳ)(Na2Al2Si2.5O9·6.2H2O)→13X型沸石(Ⅱ)和13X型沸石(Ⅲ)→13X型沸石(Ⅰ)和13X型沸石(Ⅲ).Hydrothermal method was employed to synthesize zeolite 13X with sodium metaaluminate, using sodium metasilicate nonahydrate, sodium hydroxide and distilled water as raw materials. In order to detailedly explore the phase transformation mechanism of zeolite 13X, the analysis of the synthesized samples＇ phase transitions, microscopic morphology evolution and group structure evolution was carried out by the characterization of x-ray diffraction （XRD）, scanning electron microscope （SEM）, fourier transform infrared spectroscopy （FT-IR） and raman spectroscopy. The results indicate that the silica （or alumina） tetrahedron skeleton of zeolite 13X has formed in the initial reaction stage. The crystallization process in fact is a phase transition process between various types of zeolite 13X, corresponding to a sequentially correction on the mole ratio of silicon and aluminum atom （n（Si/Al）） in zeolite skeleton. With the extension of time, n（Si/A1） decreased first, and then increased, representing a phase transformation process from positive phase transformation to inverse phase transformation. The total transformation process is shown as follows： zeolite 13X（ I ） （Na1.84 [（Al2Si4）O11.92]·7H2O）→zeolite 13X（ II ） （Na2[Al2Si3.3O10.6]·7H2O） ＋zeolite 13X（Ⅲ （Na2.06Al2Si3. 8O11.6·8H2O）→zeolite 13X（IV） （Na2Al2Si2. 5O9·6.2H2O）→zeolite 13X（Ⅱ）＋ zeolite 13X（Ⅲ）→zeolite 13X（Ⅰ）→zeolite 13X（Ⅲ）.

关 键 词：水热法 13X型沸石 物相演化 正相变 逆相变 

分 类 号：TQ170.9[化学工程—硅酸盐工业]