Mesoporous aluminosilicates with ordered hexagonal structure, strong acidity, and extraordinary hydrothermal stability at high temperatures. Steam-stable MSU-S aluminosilicate mesostructures assembled from zeolite ZSM-5 and zeolite beta seeds. Steam-stable aluminosilicate mesostructures assembled from zeolite type Y seeds. Structure of a surfactant-templated silicate framework in the absence of 3D crystallinity. Molecularly ordered inorganic frameworks in layered silicate surfactant mesophases. Ordered micro/mesoporous composite prepared as thin films. Composites of micro- and mesoporous materials: Simultaneous syntheses of MFI/MCM-41 like phases by a mixed template approach. Molecular or supramolecular templating: defining the role of surfactant chemistry in the formation of microporous and mesoporous molecular sieves. Comparison of disordered mesoporous aluminosilicates with highly ordered Al-MCM-41 on stability, acidity and catalytic activity. A detailed study of thermal, hydrothermal, and mechanical stabilities of a wide range of surfactant assembled mesoporous silicas. Disintegration of mesoporous structures of MCM-41 and MCM-48 in water. Triblock copolymer syntheses of mesoporous silica with periodic 50 to 300 angstrom pores. Disordered molecular sieve with branched mesoporous channel network. A neutral templating route to mesoporous molecular sieves. Ordered mesoporous molecular-sieves synthesized by a liquid-crystal template mechanism. From microporous to mesoporous molecular sieve materials and their use in catalysis. The hydrothermal synthesis of zeolites: history and development from the earliest days to the present time. The synthesis of the crystalline aluminosilicate materials with tunable mesoporosity and strong acidity has potentially important technological implications for catalytic reactions of large molecules, whereas conventional mesoporous materials lack hydrothermal stability and acidity.Ĭundy, C. The XRD patterns and electron micrographs of the samples taken during crystallization clearly showed the evolution of the mesoporous structure concomitantly to the crystallization of zeolite frameworks. The mesoporous zeolite exhibited a narrow, small-angle XRD peak, which is characteristic of the short-range correlation between mesopores, similar to disordered wormhole-like mesoporous materials 4, 5. The mesopore diameters could be uniformly tailored, similar to ordered mesoporous silica with amorphous frameworks 3. The analyses show that the present method is suitable as a direct synthesis route to highly mesoporous zeolites. The zeolite products were characterized by a complementary combination of X-ray diffraction (XRD), nitrogen sorption, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). ![]() In the present work, zeolites were synthesized by adding a rationally designed amphiphilic organosilane surfactant to conventional alkaline zeolite synthesis mixtures. ![]() ![]() Zeolites are a family of crystalline aluminosilicate materials widely used as shape-selective catalysts, ion exchange materials, and adsorbents for organic compounds 1, 2.
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