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利用简单微乳液自组装体系,制备了介孔二氧化硅与Y型或Ti-MWW沸石晶体复合形成的沸石/介孔二氧化硅微球(ZMMS).硅源正硅酸四丁酯与阳离子型季铵盐表面活性剂形成稳定的O/W微乳液形成大颗粒,沸石颗粒由于疏水作用而进入油相,同时,季铵盐表面活性剂和正硅酸四丁酯组装形成介孔材料.优化合成条件可以有效控制复合微球的沸石/介孔二氧化硅质量比(0～2.3)和直径(186～965μm).两种沸石/介孔二氧化硅复合微球材料的介孔孔径分别为3.98 nm(Y型沸石)和3.75 nm(Ti-MWW型沸石).Ti-MWW沸石/介孔二氧化硅复合微球在液相催化环氧化反应中表现出良好的机械强度,并且能够达到与Ti-MWW沸石原粉相当的催化活性.
The zeolite / mesoporous silica microspheres (ZMMS) formed by the combination of mesoporous silica with Y-type or Ti-MWW zeolite were prepared by using the simple microemulsion self-assembly system. Type quaternary ammonium surfactants form stable O / W microemulsions to form large particles, the zeolite particles enter the oil phase due to hydrophobic interactions, and the quaternary ammonium surfactant and tetrabutyl orthosilicate assemble to form mesoporous materials. The synthesis conditions can effectively control the zeolite / mesoporous silica mass ratio (0-2.3) and diameter (186-965μm) of the composite microspheres.The mesopores of the two zeolite / mesoporous silica composite microspheres were 3.98 nm (Y zeolite) and 3.75 nm (Ti-MWW zeolite) .Ti-MWW zeolite / mesoporous silica composite microspheres showed good mechanical strength in liquid-phase catalytic epoxidation and reached Catalytic activity comparable to Ti-MWW zeolite powder.