A novel method for increasing the conversion and optimizing the product distribution over the catalyst of zeolite Y modified by MFI aluminosilicate precursors in the reaction of benzene alkylation with isopropanol is ...A novel method for increasing the conversion and optimizing the product distribution over the catalyst of zeolite Y modified by MFI aluminosilicate precursors in the reaction of benzene alkylation with isopropanol is reported. The catalyst(PASP MFI/Y) is prepared from the impregnation of zeolite Y with preformed MFI aluminosilicate nanoclusters. The characterization of temperature-programmed desorption of ammonia shows that the PASP MFI/Y exhibits a stronger acidity than Y zeolite does. The catalytic results show that the PASP MFI/Y exhibits a more excellent activity(conversion for isopropanol and toluene) and shape selectivity(p- and m-cymene) in the reaction than zeolite Y.展开更多
The acidic strength of ordered mesoporous aluminosilicates of MAS-2, MAS-3, MAS-7 and MAS-9 and mi-croporous crystals of Y, L, beta, and ZSM-5 zeolites was systemically investigated by temperature-programmed desorptio...The acidic strength of ordered mesoporous aluminosilicates of MAS-2, MAS-3, MAS-7 and MAS-9 and mi-croporous crystals of Y, L, beta, and ZSM-5 zeolites was systemically investigated by temperature-programmed desorption of ammonia (NH3-TPD). Due to the use of preformed zeolite precursors of Y, L, beta and ZSM-5, the ordered mesoporous aluminosilicates with distinguished acidic strength were obtained, being dependent on the type of preformed zeolite precursors. Therefore, the acidic strength of these mesoporous aluminosilicates could be tai-lored and controlled.展开更多
Cu-incorporated ordered hexagonal mesoporous silicates （Cu-MCM-41） with spheres-within-a-sphere hollow structure have been synthesized using thermoreversible polymer hydrogel methylcellulose （MC） and cationic surf...Cu-incorporated ordered hexagonal mesoporous silicates （Cu-MCM-41） with spheres-within-a-sphere hollow structure have been synthesized using thermoreversible polymer hydrogel methylcellulose （MC） and cationic surfactant as co-templates, which have been characterized by scanning electron micrograph （SEM）, X-ray diffraction （XRD）, transmission electron micrograph （TEM）, and N2 adsorption-desorption isotherms. The obtained results indicate that the morphology of Cu-incorporated MCM-41 materials is ＂spheres-within-a-sphere＂ hollow structure, which is very similar to that of the alveolus. In benzene hydroxylation with H2O2, the hollow spheres show much higher catalytic activity than particles of Cu-MCM-41.展开更多
文摘A novel method for increasing the conversion and optimizing the product distribution over the catalyst of zeolite Y modified by MFI aluminosilicate precursors in the reaction of benzene alkylation with isopropanol is reported. The catalyst(PASP MFI/Y) is prepared from the impregnation of zeolite Y with preformed MFI aluminosilicate nanoclusters. The characterization of temperature-programmed desorption of ammonia shows that the PASP MFI/Y exhibits a stronger acidity than Y zeolite does. The catalytic results show that the PASP MFI/Y exhibits a more excellent activity(conversion for isopropanol and toluene) and shape selectivity(p- and m-cymene) in the reaction than zeolite Y.
基金the National Natural Science Foundation of China (Nos. 29825108, 20173022 and 20121103), the Major State Basic Research Development Program (No. 20000077507) and the National Advanced Materials Committee of China.
文摘The acidic strength of ordered mesoporous aluminosilicates of MAS-2, MAS-3, MAS-7 and MAS-9 and mi-croporous crystals of Y, L, beta, and ZSM-5 zeolites was systemically investigated by temperature-programmed desorption of ammonia (NH3-TPD). Due to the use of preformed zeolite precursors of Y, L, beta and ZSM-5, the ordered mesoporous aluminosilicates with distinguished acidic strength were obtained, being dependent on the type of preformed zeolite precursors. Therefore, the acidic strength of these mesoporous aluminosilicates could be tai-lored and controlled.
基金Project supported by the National Natural Science Foundation of China, the Major State Basic Research Development Program of China （Nos. 2004CB217804 and 2003CB615802）, and Ministry of Education, China.
文摘Cu-incorporated ordered hexagonal mesoporous silicates （Cu-MCM-41） with spheres-within-a-sphere hollow structure have been synthesized using thermoreversible polymer hydrogel methylcellulose （MC） and cationic surfactant as co-templates, which have been characterized by scanning electron micrograph （SEM）, X-ray diffraction （XRD）, transmission electron micrograph （TEM）, and N2 adsorption-desorption isotherms. The obtained results indicate that the morphology of Cu-incorporated MCM-41 materials is ＂spheres-within-a-sphere＂ hollow structure, which is very similar to that of the alveolus. In benzene hydroxylation with H2O2, the hollow spheres show much higher catalytic activity than particles of Cu-MCM-41.
