The development of metal oxides with specific facet exposure for better catalytic performance in targeted applications has been well-documented.However,the understanding of surface structure-activity correlation is s...The development of metal oxides with specific facet exposure for better catalytic performance in targeted applications has been well-documented.However,the understanding of surface structure-activity correlation is severely hindered by the current poor resolution of conventional surface characterization tools.In this mini-review,some of the latest research developments on the characterization of the surface structure and properties of faceted ZnO and TiO_(2)by probe-assisted nuclear magnetic resonance spectroscopy(NMR)are discussed.展开更多
A series of MCM 41 molecular sieves have been prepared on an industrial scale, and the effect of preparation factors such as aging temperature, pH values on the structure and pore distribution of the MCM 41 product ...A series of MCM 41 molecular sieves have been prepared on an industrial scale, and the effect of preparation factors such as aging temperature, pH values on the structure and pore distribution of the MCM 41 product have been studied by using X ray diffraction(XRD), thermogravimetric(TG) and electron microscopy(TEM). It is shown that the pH values have a significant effect on the crystallinity of the synthesized product. Under proper conditions, the MCM 41 prepared on an industrial scale has the same performance as the samples prepared on an Lab scale. The prepared MCM 41 was used as a modifier of zeolite Y for fluid catalytic cracking(FCC) of residual oil. It is shown that the addition of the MCM 41 in the zeolite Y catalyst increases the pore size, and surface area of the catalysts, which helps to increase the yield of gasoline and diesel and decrease the production of gaseous product and carbon deposition in the catalyst. The better performance of the MCM 41 modified zeolite Y catalyst is believed to be due to its adjustment on the acidity and increase of the pore size.展开更多
基金the National Natural Science Foundation of China(21902138)the Natural Science Fund of Guangdong Province(2021A1515010064)+1 种基金the Hong Kong Research Grants Council(21301719,11300020,and 11305721)Chow Sang Sang Group Research Fund(9229063)sponsored by Chow Sang Sang Holdings International Limited for funding support.
文摘The development of metal oxides with specific facet exposure for better catalytic performance in targeted applications has been well-documented.However,the understanding of surface structure-activity correlation is severely hindered by the current poor resolution of conventional surface characterization tools.In this mini-review,some of the latest research developments on the characterization of the surface structure and properties of faceted ZnO and TiO_(2)by probe-assisted nuclear magnetic resonance spectroscopy(NMR)are discussed.
文摘A series of MCM 41 molecular sieves have been prepared on an industrial scale, and the effect of preparation factors such as aging temperature, pH values on the structure and pore distribution of the MCM 41 product have been studied by using X ray diffraction(XRD), thermogravimetric(TG) and electron microscopy(TEM). It is shown that the pH values have a significant effect on the crystallinity of the synthesized product. Under proper conditions, the MCM 41 prepared on an industrial scale has the same performance as the samples prepared on an Lab scale. The prepared MCM 41 was used as a modifier of zeolite Y for fluid catalytic cracking(FCC) of residual oil. It is shown that the addition of the MCM 41 in the zeolite Y catalyst increases the pore size, and surface area of the catalysts, which helps to increase the yield of gasoline and diesel and decrease the production of gaseous product and carbon deposition in the catalyst. The better performance of the MCM 41 modified zeolite Y catalyst is believed to be due to its adjustment on the acidity and increase of the pore size.
