The effect of crystal size of USY zeolite on the performance of hydro-upgrading catalysts for treating catalytically cracked(FCC) LCO(light cycle oil) was studied.Three W-Ni catalysts supported on USY zeolites with di...The effect of crystal size of USY zeolite on the performance of hydro-upgrading catalysts for treating catalytically cracked(FCC) LCO(light cycle oil) was studied.Three W-Ni catalysts supported on USY zeolites with different crystal sizes and Al2O3 were prepared by impregnation method.The catalysts were characterized by XRD and BET methods,and evaluated in a micro-reactor using tetralin as the model compound and in an 100-mL hydrogenation test unit using FCC LCO as the feedstock.By contrast,catalyst made from smaller crystal-size USY zeolite had higher external surface area and shorter pore length,having more hydrogenation activity sites and short contact time of reactant molecules with acidity sites.The evaluation results showed that the catalyst prepared on the basis of small crystal-size USY zeolite had higher tetralin conversion and better hydro-upgrading performance for treating FCC LCO.展开更多
A catalyst is a substance that alters the rate of a reaction. The process of catalysis is essential to the modem day manufacturing industry, mainly in FCC （Fluid Catalytic Cracking） process units. However, long-term...A catalyst is a substance that alters the rate of a reaction. The process of catalysis is essential to the modem day manufacturing industry, mainly in FCC （Fluid Catalytic Cracking） process units. However, long-term exploitation of oil and gas processing catalysts leads to formation of carbon- and sulfur-containing structures of coke and dense products on the catalyst surface. They block reactive catalyst sites and reduce the catalytic activity. The main advantage of radiation processing by EB （electron beam） and gamma rays is chain cracking reaction in crude oil. Otherwise, under exposure to ionize radiation, considerable structure modification of equilibrium silica-alumina catalyst from FCC process may occur, in addition to the removal of impurities. The conditions applied in the irradiation range （20-150 kGy） of gamma rays and EB were not sufficient to alter the structure of the catalyst, whether for removal of the contaminant nickel, a major contaminant of the FCC catalyst, either to rupture of the crystalline structure either for the future reutilization of chemical elements. ATR-FTIR （Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy and EDXRFS （Energy Dispersive X-Ray Fluorescence Spectrometry） analysis were used to characterize and evaluate effects of radiation processing on equilibrium catalysts purification. To evaluate and comprehend the reactive catalyst sites, SEM （Scanning Electron Microscopy） and particle size distribution analyses were carried out.展开更多
A cobalt-based catalyst was directly photo-deposited on the surface of a widely used n-type nano-structured semiconductor(TiO_(2)).Different thicknesses of the TiO 2 films as well as different time of photo-deposition...A cobalt-based catalyst was directly photo-deposited on the surface of a widely used n-type nano-structured semiconductor(TiO_(2)).Different thicknesses of the TiO 2 films as well as different time of photo-deposition of the Co-based catalyst on TiO_(2) films have been optimized.It was found that the electrode with 3 layers of TiO_(2) film(in 8 m thickness) and 1 hour photo-deposition of the cobalt-based catalyst by light irradiation from a 500 W Xenon lamp gave the highest current density(~5 mA/cm^(2)).Using this cobalt-modified TiO_(2) film as a working electrode in an electrochemical device,highly efficient water oxidation has been demonstrated in a pH 7.0 aqueous solution with low overpotential.展开更多
基金support from the China National Petroleum Corporation (CNPC) (2011B-2304-0305)
文摘The effect of crystal size of USY zeolite on the performance of hydro-upgrading catalysts for treating catalytically cracked(FCC) LCO(light cycle oil) was studied.Three W-Ni catalysts supported on USY zeolites with different crystal sizes and Al2O3 were prepared by impregnation method.The catalysts were characterized by XRD and BET methods,and evaluated in a micro-reactor using tetralin as the model compound and in an 100-mL hydrogenation test unit using FCC LCO as the feedstock.By contrast,catalyst made from smaller crystal-size USY zeolite had higher external surface area and shorter pore length,having more hydrogenation activity sites and short contact time of reactant molecules with acidity sites.The evaluation results showed that the catalyst prepared on the basis of small crystal-size USY zeolite had higher tetralin conversion and better hydro-upgrading performance for treating FCC LCO.
文摘A catalyst is a substance that alters the rate of a reaction. The process of catalysis is essential to the modem day manufacturing industry, mainly in FCC （Fluid Catalytic Cracking） process units. However, long-term exploitation of oil and gas processing catalysts leads to formation of carbon- and sulfur-containing structures of coke and dense products on the catalyst surface. They block reactive catalyst sites and reduce the catalytic activity. The main advantage of radiation processing by EB （electron beam） and gamma rays is chain cracking reaction in crude oil. Otherwise, under exposure to ionize radiation, considerable structure modification of equilibrium silica-alumina catalyst from FCC process may occur, in addition to the removal of impurities. The conditions applied in the irradiation range （20-150 kGy） of gamma rays and EB were not sufficient to alter the structure of the catalyst, whether for removal of the contaminant nickel, a major contaminant of the FCC catalyst, either to rupture of the crystalline structure either for the future reutilization of chemical elements. ATR-FTIR （Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy and EDXRFS （Energy Dispersive X-Ray Fluorescence Spectrometry） analysis were used to characterize and evaluate effects of radiation processing on equilibrium catalysts purification. To evaluate and comprehend the reactive catalyst sites, SEM （Scanning Electron Microscopy） and particle size distribution analyses were carried out.
基金supported by Swedish Energy Agency,the Knutand Alice Wallenberg Foundation,China Scholarship Council (CSC)the Natural Natural Science Foundation of China (21120102036)the National Basic Research Program of China (2009CB220009)
文摘A cobalt-based catalyst was directly photo-deposited on the surface of a widely used n-type nano-structured semiconductor(TiO_(2)).Different thicknesses of the TiO 2 films as well as different time of photo-deposition of the Co-based catalyst on TiO_(2) films have been optimized.It was found that the electrode with 3 layers of TiO_(2) film(in 8 m thickness) and 1 hour photo-deposition of the cobalt-based catalyst by light irradiation from a 500 W Xenon lamp gave the highest current density(~5 mA/cm^(2)).Using this cobalt-modified TiO_(2) film as a working electrode in an electrochemical device,highly efficient water oxidation has been demonstrated in a pH 7.0 aqueous solution with low overpotential.
