A novel coprecipitation-reduction process has been proposed for preparing highly selective Cu/ZnO/Al 2O 3 catalysts for methanol synthesis from CO 2 hydrogenation. Compared to the catalysts prepared by the conventiona...A novel coprecipitation-reduction process has been proposed for preparing highly selective Cu/ZnO/Al 2O 3 catalysts for methanol synthesis from CO 2 hydrogenation. Compared to the catalysts prepared by the conventional method, the new catalysts prepared via the new method exhibit much higher BET surface area and pore size, much smaller crystallite size and higher catalytic activity and selectivity in CO 2 hydrogenation to methanol. It is also found that the molar ratio of Cu + to Cu 0 on the surface of the catalyst obtained by coprecipitation-reduction is much higher than that on the reduced catalyst obtained by the conventional method, which could be crucial for its high activity and selectivity for catalytic hydrogenation of CO 2 to methanol.展开更多
A novel process for preparation of micrometer-scale functional materials without organic templates has been demonstrated. Titania spheroid with a tailored core-shell structure and high ordered mesoposity has been mani...A novel process for preparation of micrometer-scale functional materials without organic templates has been demonstrated. Titania spheroid with a tailored core-shell structure and high ordered mesoposity has been manipulated in the ethanol hydrothermal system containing ammonia sulfate as a dispersant. Titania spheroid with a mean diameter of 3.6 μm and a high specific surface area of 266 m 2/g has been synthesized by precipitating titanium tetrachloride with ammonia gas released from hydrolysis of urea at a high temperature. A special core-shell structure with a 100 nm thin shell and a 300 nm spacing strip interiors has been characterized by SEM & TEM. The catalytic performance of the titania spheoid supported WO 3 catalyst for the selective oxidation of cyclopentene(CPE) to glutaraldehyde(GA) has been investigated. The WO 3/TiO 2 spheroid catalyst displays an exciting prospect for good selectivity(72.9%) toward GA and a high GA yield(about 70%) for the titled reaction using aqueous H 2O 2 as the oxidant.展开更多
文摘A novel coprecipitation-reduction process has been proposed for preparing highly selective Cu/ZnO/Al 2O 3 catalysts for methanol synthesis from CO 2 hydrogenation. Compared to the catalysts prepared by the conventional method, the new catalysts prepared via the new method exhibit much higher BET surface area and pore size, much smaller crystallite size and higher catalytic activity and selectivity in CO 2 hydrogenation to methanol. It is also found that the molar ratio of Cu + to Cu 0 on the surface of the catalyst obtained by coprecipitation-reduction is much higher than that on the reduced catalyst obtained by the conventional method, which could be crucial for its high activity and selectivity for catalytic hydrogenation of CO 2 to methanol.
文摘A novel process for preparation of micrometer-scale functional materials without organic templates has been demonstrated. Titania spheroid with a tailored core-shell structure and high ordered mesoposity has been manipulated in the ethanol hydrothermal system containing ammonia sulfate as a dispersant. Titania spheroid with a mean diameter of 3.6 μm and a high specific surface area of 266 m 2/g has been synthesized by precipitating titanium tetrachloride with ammonia gas released from hydrolysis of urea at a high temperature. A special core-shell structure with a 100 nm thin shell and a 300 nm spacing strip interiors has been characterized by SEM & TEM. The catalytic performance of the titania spheoid supported WO 3 catalyst for the selective oxidation of cyclopentene(CPE) to glutaraldehyde(GA) has been investigated. The WO 3/TiO 2 spheroid catalyst displays an exciting prospect for good selectivity(72.9%) toward GA and a high GA yield(about 70%) for the titled reaction using aqueous H 2O 2 as the oxidant.
