Pd and /or Cu - La2O3/SiO2 catalysts were prepared by Pd and/or Cu supported on La2O3/SiO2 with impregnation The capacities of catalysts reduction and the performance of reaction were studied by H2-TPR and hydrogenati...Pd and /or Cu - La2O3/SiO2 catalysts were prepared by Pd and/or Cu supported on La2O3/SiO2 with impregnation The capacities of catalysts reduction and the performance of reaction were studied by H2-TPR and hydrogenation of CO2 The results of H2-TPR indicate that increasing the content of CuO is advantageous to the reduction of high dispersing CuO, but adding La2O3 hinder the reduction of high dispersing CuO It was found that Pd-Cu alloy formed while Pd, Cu impregnated on La2O3/SiO2 The results of hydrogenation of CO2 indicate that CO2 conversion is promoted by adding La2O3 increasing the content of CuO The thermal stablity of methanol formation was improved by adding La2O3 Aldehyde can be obtained when Pd-Cu were used as active components, and the production of methanol was related to the content of Pd loaded on the展开更多
Co and Mo bimetallic nitrides supported on Mg（Al）O, MgO and γ-Al2O3 were prepared in temperatureprogrammed reactions with NH3. The surface morphology, chemical composition and catalytic activity for NH3 decompositi...Co and Mo bimetallic nitrides supported on Mg（Al）O, MgO and γ-Al2O3 were prepared in temperatureprogrammed reactions with NH3. The surface morphology, chemical composition and catalytic activity for NH3 decomposition on the supported Co and Mo bimetallic nitrides were studied by X-ray diffractometer （XRD）, NH3 temperature-programmed desorption and mass spectrometer （NH3-TPD-MS）, temperature-programmed desorption and mass spectrometer （TPD-MS）, H2 temperature-programmed surface reaction （H2-TPSR） and activity test. The phases of Co3Mo3N and MoN could be formed on Mg（Al）O, MgO and Al2O3 during the nitridation, and they might be more uniformly dispersed on Mg（Al）O and MgO than on γ-Al2O3. Transition metallic nitrides are generally considered as potential catalysts for hydrogen-involving reactions due to the entrance of hydrogen atoms into subsurface and the lattice of metallic nitrides. The diffusion of nitrogen in the bulk and the structure transformation of Co and Mo nitride compounds occur during NH3-TPD, but the supported Co and Mo bimetallic nitrides are not easily reduced at H2 atmosphere. Co3Mo3N/Mg（Al）O catalyst exhibits the highest activity, while Co3Mo3N/Al2O3 exhibits the lowest activity for NH3 decomposition. Furthermore, the catalytic activity of Co and Mo bimetallic nitrides is not only much higher than that of supported single metallic nitride, but also highly dependent upon the surface acidity and BET surface area of support.展开更多
文摘Pd and /or Cu - La2O3/SiO2 catalysts were prepared by Pd and/or Cu supported on La2O3/SiO2 with impregnation The capacities of catalysts reduction and the performance of reaction were studied by H2-TPR and hydrogenation of CO2 The results of H2-TPR indicate that increasing the content of CuO is advantageous to the reduction of high dispersing CuO, but adding La2O3 hinder the reduction of high dispersing CuO It was found that Pd-Cu alloy formed while Pd, Cu impregnated on La2O3/SiO2 The results of hydrogenation of CO2 indicate that CO2 conversion is promoted by adding La2O3 increasing the content of CuO The thermal stablity of methanol formation was improved by adding La2O3 Aldehyde can be obtained when Pd-Cu were used as active components, and the production of methanol was related to the content of Pd loaded on the
文摘Co and Mo bimetallic nitrides supported on Mg（Al）O, MgO and γ-Al2O3 were prepared in temperatureprogrammed reactions with NH3. The surface morphology, chemical composition and catalytic activity for NH3 decomposition on the supported Co and Mo bimetallic nitrides were studied by X-ray diffractometer （XRD）, NH3 temperature-programmed desorption and mass spectrometer （NH3-TPD-MS）, temperature-programmed desorption and mass spectrometer （TPD-MS）, H2 temperature-programmed surface reaction （H2-TPSR） and activity test. The phases of Co3Mo3N and MoN could be formed on Mg（Al）O, MgO and Al2O3 during the nitridation, and they might be more uniformly dispersed on Mg（Al）O and MgO than on γ-Al2O3. Transition metallic nitrides are generally considered as potential catalysts for hydrogen-involving reactions due to the entrance of hydrogen atoms into subsurface and the lattice of metallic nitrides. The diffusion of nitrogen in the bulk and the structure transformation of Co and Mo nitride compounds occur during NH3-TPD, but the supported Co and Mo bimetallic nitrides are not easily reduced at H2 atmosphere. Co3Mo3N/Mg（Al）O catalyst exhibits the highest activity, while Co3Mo3N/Al2O3 exhibits the lowest activity for NH3 decomposition. Furthermore, the catalytic activity of Co and Mo bimetallic nitrides is not only much higher than that of supported single metallic nitride, but also highly dependent upon the surface acidity and BET surface area of support.
