The copper based catalysts, CuO/T-Al2O3, CuO/y-Al2O3-cordierite （Cord） and CuO/Cord, were prepared by impregnation method. The catalytic activity of the catalysts was tested in absence and presence of water vapor,an...The copper based catalysts, CuO/T-Al2O3, CuO/y-Al2O3-cordierite （Cord） and CuO/Cord, were prepared by impregnation method. The catalytic activity of the catalysts was tested in absence and presence of water vapor,and the catalysts were characterized. Temperature program desorption （TPD） experiments or toluene and water on the catalysts were carried out. The influence of water vapor on the activity of the catalysts was discussed. Results showed that addition of the water vapor has a significant negative effect on the catalytic activity of the catalysts.The higher the concentration of the Water vapor in feed steam was, the lower the catalytic activity of the copper based catalysts became, which could be mainly ascribed to the competition of water molecules with toluene molecules for adsorption on the catalyst surfaces. TPD experiments showed that the strength of the interaction between water molecules and three catalysts followed the order： CuO/γ-Al2O3〉CuO/γ-Al2O3-Cord〉CuO/Cord. As a consequence of that, the degree of degradation in the catalytic activity of these three catalysts by the water vapor followed the order： CuO/γ-Al2O3〉CuO/y-Al2O3-Cord〉CuO/Cord. However, the negative effect of the water vapor was reversible.展开更多
The nano ZrO2-supported copper-based catalysts for methane combustion were investigated by means of N2 adsorption, TEM, XRD, H2-TPR techniques and the test of methane oxidation. Two kinds of ZrO2 were used as support,...The nano ZrO2-supported copper-based catalysts for methane combustion were investigated by means of N2 adsorption, TEM, XRD, H2-TPR techniques and the test of methane oxidation. Two kinds of ZrO2 were used as support, one （ZrO2-1） was obtained from the commercial ZrO2 and the other （ZrO2-2） was issued from the thermal decomposition of zirconium nitrate. It was found that the CuO/ZrO2-2 catalyst was more active than CuO/ZrO2-1. N2 adsorption, H2-TPR and XRD measurements showed that larger surface area, better reduction property, presence of tetragonal ZrO2 and higher dispersion of active component for CuO/ZrO2-2 than that of CuO/ZrO2-1. These factors could be the dominating reasons for its higher activity for methane combustion.展开更多
Various Cu/ZnO/Al2O3 catalysts have been synthesized by different aluminum emulsions as aluminum sources and their pertormances tor methanol synthesis from syngas have been investigated. The influences of preparation ...Various Cu/ZnO/Al2O3 catalysts have been synthesized by different aluminum emulsions as aluminum sources and their pertormances tor methanol synthesis from syngas have been investigated. The influences of preparation methods of aluminum emulsions on physicochemical and catalytic properties of catalysts were studied by XRD, SEM, XPS,N2 adsorption-desorption techniques and methanol synthesis from syngas. The preparation methods of aluminum emulsions were found to influence the catalytic activity, CuO crystallite size, surface area and Cu0 surface area and reduction process. The results show that the catalyst CN using the aluminum source prepared by addition the ammonia into the aluminum nitrate （NP） exhibited the best catalytic performance for methanol synthesis from syngas.展开更多
A novel strategy to synthesize copper-based nanoparticles supported on carbon nitride(C3 N4) was developed by popping of mixture containing C3 N4 and cupric nitrate. Characterizations such as X-ray photoelectron spect...A novel strategy to synthesize copper-based nanoparticles supported on carbon nitride(C3 N4) was developed by popping of mixture containing C3 N4 and cupric nitrate. Characterizations such as X-ray photoelectron spectroscopy(XPS) and X-ray diffraction(XRD) indicate that the structure of g-C3 N4 maintained although a popping process occurred. High resolution transmission electronic microscopy(HRTEM) characterization illustrated that copper-based nanoparticles with diameter of < 1 nm were well distributed on g-C3 N4. This kind of copper catalyst exhibits high catalytic activity and selectivity in arylation of pyrazole, a simple and effect strategy to construct C-N bond in organic chemistry.According to the results of control experiments and characterizations, cuprous oxide should be the catalytic active phase in the supported coperbased catalyst.展开更多
基金Supported by the National-Natural Science Foundation of China （20936001）, the Natural Science Foundation of Guangdong Province, and the State Key Lab of Subtropical Building Science, South China University of Technology （x2yj C709028Z）.
文摘The copper based catalysts, CuO/T-Al2O3, CuO/y-Al2O3-cordierite （Cord） and CuO/Cord, were prepared by impregnation method. The catalytic activity of the catalysts was tested in absence and presence of water vapor,and the catalysts were characterized. Temperature program desorption （TPD） experiments or toluene and water on the catalysts were carried out. The influence of water vapor on the activity of the catalysts was discussed. Results showed that addition of the water vapor has a significant negative effect on the catalytic activity of the catalysts.The higher the concentration of the Water vapor in feed steam was, the lower the catalytic activity of the copper based catalysts became, which could be mainly ascribed to the competition of water molecules with toluene molecules for adsorption on the catalyst surfaces. TPD experiments showed that the strength of the interaction between water molecules and three catalysts followed the order： CuO/γ-Al2O3〉CuO/γ-Al2O3-Cord〉CuO/Cord. As a consequence of that, the degree of degradation in the catalytic activity of these three catalysts by the water vapor followed the order： CuO/γ-Al2O3〉CuO/y-Al2O3-Cord〉CuO/Cord. However, the negative effect of the water vapor was reversible.
文摘The nano ZrO2-supported copper-based catalysts for methane combustion were investigated by means of N2 adsorption, TEM, XRD, H2-TPR techniques and the test of methane oxidation. Two kinds of ZrO2 were used as support, one （ZrO2-1） was obtained from the commercial ZrO2 and the other （ZrO2-2） was issued from the thermal decomposition of zirconium nitrate. It was found that the CuO/ZrO2-2 catalyst was more active than CuO/ZrO2-1. N2 adsorption, H2-TPR and XRD measurements showed that larger surface area, better reduction property, presence of tetragonal ZrO2 and higher dispersion of active component for CuO/ZrO2-2 than that of CuO/ZrO2-1. These factors could be the dominating reasons for its higher activity for methane combustion.
文摘Various Cu/ZnO/Al2O3 catalysts have been synthesized by different aluminum emulsions as aluminum sources and their pertormances tor methanol synthesis from syngas have been investigated. The influences of preparation methods of aluminum emulsions on physicochemical and catalytic properties of catalysts were studied by XRD, SEM, XPS,N2 adsorption-desorption techniques and methanol synthesis from syngas. The preparation methods of aluminum emulsions were found to influence the catalytic activity, CuO crystallite size, surface area and Cu0 surface area and reduction process. The results show that the catalyst CN using the aluminum source prepared by addition the ammonia into the aluminum nitrate （NP） exhibited the best catalytic performance for methanol synthesis from syngas.
基金supported the following funders: One Hundred Talent Project of Hebei Province (Grant No. E2016100015)National Natural Science Foundation of China (No. 21773053)+2 种基金Hebei provincial Natural Science Foundation (No. B2017201084)Hebei Provincial Technology Foundation for High-level talents (No. CL201601)the science technology research and development guidance program project of Baoding City (No. 16ZF027)
文摘A novel strategy to synthesize copper-based nanoparticles supported on carbon nitride(C3 N4) was developed by popping of mixture containing C3 N4 and cupric nitrate. Characterizations such as X-ray photoelectron spectroscopy(XPS) and X-ray diffraction(XRD) indicate that the structure of g-C3 N4 maintained although a popping process occurred. High resolution transmission electronic microscopy(HRTEM) characterization illustrated that copper-based nanoparticles with diameter of < 1 nm were well distributed on g-C3 N4. This kind of copper catalyst exhibits high catalytic activity and selectivity in arylation of pyrazole, a simple and effect strategy to construct C-N bond in organic chemistry.According to the results of control experiments and characterizations, cuprous oxide should be the catalytic active phase in the supported coperbased catalyst.
基金supported by Fundamental Research Program of Shanxi Province(202203021221303)Science and Technology Major Project of Shanxi Province(202005D121002)The Central Project Guide Local Science and Technology for Development(2020SW26)。
