硅胶原位合成ZSM-5分子筛及其催化性能的研究

以正丁胺为模板剂，采用水热晶化法在固体硅胶小球上原位合成了ZSM-5分子筛。考察了晶化温度、晶化时间、初始凝胶硅铝比及H2O/ SiO2、BuNH2/ SiO2、OH-/SiO2对ZSM-5相对结晶度的影响，得到了ZSM 5的合成化学规律。采用XRD、SEM、FT IR及N2吸附手段对固体硅胶小球上原位合成的复合结构分子筛进行了表征。结果表明，这种材料具有介孔和微孔的复合结构特征，而且很好地保持了硅胶小球的形貌。以大庆VGO为原料，在重油微反装置上对该复合结构分子筛进行催化性能评价。结果表明，使用硅胶原位合成的ZSM-5分子筛可显著提高低碳烯烃选择性和收率。

In-situ synthesis of ZSM-5 on silica gel and studies on its catalytic activity

ZSM-5 was in-situ synthesized on silica gel using n-butylamine as the template and characterized by XRD, SEM, FT-IR and N₂ adsorption. The results indicated that the synthesized sample not only has a composite structure with ZSM-5 and silica gel, but also retains the shape of silica gel microsphere. To obtain detailed information on the rules of synthesized chemistry, the effects of SiO₂/Al₂O₃ of initial gel, H₂O/SiO₂, BuNH₂/SiO₂, OH⁻/SiO₂, crystallization time and crystallization temperature on ZSM-5 crystallinity were systematically studied. The composite materials were tested in a micro fixed-bed reactor, using Daqing Vacuum Gasoline Oil (VGO) as the feedstock. The results indicated that the composite structure zeolite yields more light olefins and has good selectivity to light olefins.