Two mixed-matrix NiMo/Al2O3 catalysts containing nano-and micro-sized zeolite Y have been prepared to explore the size effect of zeolite Y particle on the hydrodesulfurization(HDS)and hydrodenitrogenation(HDN)acti...Two mixed-matrix NiMo/Al2O3 catalysts containing nano-and micro-sized zeolite Y have been prepared to explore the size effect of zeolite Y particle on the hydrodesulfurization(HDS)and hydrodenitrogenation(HDN)activities of fluid catalytic cracking(FCC)diesel.They were characterized by SEM,BET,XRD,H2-TPR,NH3-TPD and HRTEM.The results show that the catalyst containing nano-sized zeolite Y possesses larger average pore diameter,higher pore volume,weaker and lesser acid sites,more easily reducible metal phases,shorter MoS2 slabs and more slab layers than the catalyst containing micro-sized zeolite Y.The catalysts were also evaluated with a high-pressure fixed-bed reactor using real FCC diesel as feed.The results display that the catalyst containing nano-sized zeolite Y bears higher HDS and HDN activities and exhibits higher relative rate constant for the removal of total sulfur or nitrogen than the one containing micro-sized zeolite.展开更多
An evidence for the synergetic effect between the stacked bed of Mo/γ-Al2O3 and Ni/γ-Al2O3 in the hydrodenitrogenation (HDN) reaction of quinoline has been provided in this paper. The synergism factor decreases wh...An evidence for the synergetic effect between the stacked bed of Mo/γ-Al2O3 and Ni/γ-Al2O3 in the hydrodenitrogenation (HDN) reaction of quinoline has been provided in this paper. The synergism factor decreases when the reaction temperature increases (280?340 ?C). The synergetic effect leads to improve the hydrogenation activity for the stacked bed compared with the single Mo/γ-Al2O3 bed, which may be attributed to the generation of hydrogen spillover on the Ni/γ-Al2O3 catalyst.展开更多
Two series of WP/Al2O3 catalyst precursors with WP mass loading in the range 18.5%—37.1% were prepared using the impregnation method and mixing method, respectively, and the catalysts were then obtained by temperatur...Two series of WP/Al2O3 catalyst precursors with WP mass loading in the range 18.5%—37.1% were prepared using the impregnation method and mixing method, respectively, and the catalysts were then obtained by temperature-programmed reduction of supported tungsten phosphate (precursor of WP/Al2O3 catatlysts) in H2 at 650℃ for 4h. The catalysts were characterized by XRD, BET, TG/DTA , XPS and 31P MAS-NMR. The activities of these catalysts were tested in the hydrodenitrogenation (HDN) of pyridine and hydrodesulfurization (HDS) of thiophene at 340℃ and 3.0MPa. The results showed that owing to the stronger interaction of the support with the active species, the precursor of WP/Al2O3 catalyst was more difficultly phosphided and a greater amount of W spe- cies was in a high valence state W6+ on the surface of the catalyst prepared by the impregnation method than that by the mixing method. 31P MAS-NMR results indicated that 31P shift from 85% H3PO4 of 2.55×10-4 for WP and 2.57 ×10-4 for WP/γ-Al2O3 catalysts prepared by mixing method. Such WP/Al2O3 catalysts showed higher HDN activi- ties and lower HDS activities than those prepared by the impregnation method under the same loading of WP. WP/γ-Al2O3 catalysts with weak interaction between support and active species were favorable for HDN reaction while the WP/γ-Al2O3 catalysts with strong interaction were favorable for HDS reaction.展开更多
Using the JQ-II high pressure hydrogenation micro-reactor unit, the reactivity of Athabasca bitumen derived heavy gas oil was studied over commercial and homemade hydrotreating catalysts. The effects of catalyst prepa...Using the JQ-II high pressure hydrogenation micro-reactor unit, the reactivity of Athabasca bitumen derived heavy gas oil was studied over commercial and homemade hydrotreating catalysts. The effects of catalyst preparation variables and the influences of operation conditions, such as pressure, temperature, hydrogen/oil ratio and space velocity were also examined. It was shown that the optimal concentrations of the active components were 5% of NiO, 20% of MoO3 and 3.5% of phosphorus (by mass), and the suitable operation conditions were determined experimentally.展开更多
The charge distribution on Ni-Mo-S active sites can affect hydrodenitrogenation(HDN)activity.In this study,a series of model Ni-Mo-S were developed with various charge distributions.For comparison,the charge distribut...The charge distribution on Ni-Mo-S active sites can affect hydrodenitrogenation(HDN)activity.In this study,a series of model Ni-Mo-S were developed with various charge distributions.For comparison,the charge distribution effects on quinoline HDN were studied.The results show that a lack of electrons and extra protons can both lower the orbital eigenvalue of the Ni-Mo-S,leading to stronger adsorption of nitrogen-containing compounds and inhibition of ammonia desorption.Electron deficiency will improve the generation of active hydrogen on the active sites but inhibit hydrogen transfer to the nitrogen compounds;extra protons can provide H^(+)to the nitrogen compounds,which will flexibly transfer between the nitrogen compound and active sites,thus improving the cleavage of the C-N bond.展开更多
The kinetics of Athabasca bitumen derived heavy gas oil over NiMo/Al2O3 catalysts were studied in a JQ-II high-pressure microscale hydrotreator unit under different operation conditions, including temperature, pressur...The kinetics of Athabasca bitumen derived heavy gas oil over NiMo/Al2O3 catalysts were studied in a JQ-II high-pressure microscale hydrotreator unit under different operation conditions, including temperature, pressure, H/O ratio and LHSV. The multi-parameter models of hydrodesulfurization and hydrodenitrogenation were proposed. The model parameters verify that the HDS and HDN reactions follow 1.5-order and 1.6-order kinetic rules, respectively. The kinetic activation energies of HDN and HDS over Com, Hom1 and Hom2 show that homemade catalysts exhibit higher activities in HDN than commercial catalyst. Using the multi-parameter kinetic model to predict the contents of sulfur and nitrogen in products is in good agreement with the experimental data.展开更多
The catalysts were prepared by the temperature programmed reaction (TPR) of MoO3 with NH3 at various temperatures in the range of 573K~973K, and their hydrodenitrogenation (HDN) activities were tested in situ.It is s...The catalysts were prepared by the temperature programmed reaction (TPR) of MoO3 with NH3 at various temperatures in the range of 573K~973K, and their hydrodenitrogenation (HDN) activities were tested in situ.It is shown that molybdenum nitrid(Mo2N) was formed above 923K and its intermediate MoO2 formed at about 573~623K under the rapid (5K/min.) TPR conditions.Mo2N is the most active species for pyridine HDN among MoO3,MoO2,MoS2,and Mo2N. Moreover,it can be promoted by adding Ni component.It is shown that the Ni/Mo2N catalyst prepared by adding some NiO into the precursor MoO3 has a steady HDN activity Which is far higher than that of the commercial sulfided NiMo/Al2O3(HR346) catalyst.展开更多
基金financially supported by the Basic Research Program'Green Chemistry and Engineering of Heavy Oil Conversion with High Efficiency' and the National Key Fundamental Research Development Project(973 Project:No.2010CB226905)
文摘Two mixed-matrix NiMo/Al2O3 catalysts containing nano-and micro-sized zeolite Y have been prepared to explore the size effect of zeolite Y particle on the hydrodesulfurization(HDS)and hydrodenitrogenation(HDN)activities of fluid catalytic cracking(FCC)diesel.They were characterized by SEM,BET,XRD,H2-TPR,NH3-TPD and HRTEM.The results show that the catalyst containing nano-sized zeolite Y possesses larger average pore diameter,higher pore volume,weaker and lesser acid sites,more easily reducible metal phases,shorter MoS2 slabs and more slab layers than the catalyst containing micro-sized zeolite Y.The catalysts were also evaluated with a high-pressure fixed-bed reactor using real FCC diesel as feed.The results display that the catalyst containing nano-sized zeolite Y bears higher HDS and HDN activities and exhibits higher relative rate constant for the removal of total sulfur or nitrogen than the one containing micro-sized zeolite.
基金supported by the State Key Development Program for Basic Research of China (No. 2010CB226905)supported by the Basic Research Program " Green Chemistry and Engineering of Heavy Oil Conversionwith High Efficiency "
文摘An evidence for the synergetic effect between the stacked bed of Mo/γ-Al2O3 and Ni/γ-Al2O3 in the hydrodenitrogenation (HDN) reaction of quinoline has been provided in this paper. The synergism factor decreases when the reaction temperature increases (280?340 ?C). The synergetic effect leads to improve the hydrogenation activity for the stacked bed compared with the single Mo/γ-Al2O3 bed, which may be attributed to the generation of hydrogen spillover on the Ni/γ-Al2O3 catalyst.
基金Supported by the National Natural Science Foundation of China (No.200273011), the National 973 Project (No.G2000048003)and the Beijing Natural Science Foundation (No.2052009).
文摘Two series of WP/Al2O3 catalyst precursors with WP mass loading in the range 18.5%—37.1% were prepared using the impregnation method and mixing method, respectively, and the catalysts were then obtained by temperature-programmed reduction of supported tungsten phosphate (precursor of WP/Al2O3 catatlysts) in H2 at 650℃ for 4h. The catalysts were characterized by XRD, BET, TG/DTA , XPS and 31P MAS-NMR. The activities of these catalysts were tested in the hydrodenitrogenation (HDN) of pyridine and hydrodesulfurization (HDS) of thiophene at 340℃ and 3.0MPa. The results showed that owing to the stronger interaction of the support with the active species, the precursor of WP/Al2O3 catalyst was more difficultly phosphided and a greater amount of W spe- cies was in a high valence state W6+ on the surface of the catalyst prepared by the impregnation method than that by the mixing method. 31P MAS-NMR results indicated that 31P shift from 85% H3PO4 of 2.55×10-4 for WP and 2.57 ×10-4 for WP/γ-Al2O3 catalysts prepared by mixing method. Such WP/Al2O3 catalysts showed higher HDN activi- ties and lower HDS activities than those prepared by the impregnation method under the same loading of WP. WP/γ-Al2O3 catalysts with weak interaction between support and active species were favorable for HDN reaction while the WP/γ-Al2O3 catalysts with strong interaction were favorable for HDS reaction.
文摘Using the JQ-II high pressure hydrogenation micro-reactor unit, the reactivity of Athabasca bitumen derived heavy gas oil was studied over commercial and homemade hydrotreating catalysts. The effects of catalyst preparation variables and the influences of operation conditions, such as pressure, temperature, hydrogen/oil ratio and space velocity were also examined. It was shown that the optimal concentrations of the active components were 5% of NiO, 20% of MoO3 and 3.5% of phosphorus (by mass), and the suitable operation conditions were determined experimentally.
基金the financial support from the Sinopec Science and Technology Department(Grant No.121014-1)。
文摘The charge distribution on Ni-Mo-S active sites can affect hydrodenitrogenation(HDN)activity.In this study,a series of model Ni-Mo-S were developed with various charge distributions.For comparison,the charge distribution effects on quinoline HDN were studied.The results show that a lack of electrons and extra protons can both lower the orbital eigenvalue of the Ni-Mo-S,leading to stronger adsorption of nitrogen-containing compounds and inhibition of ammonia desorption.Electron deficiency will improve the generation of active hydrogen on the active sites but inhibit hydrogen transfer to the nitrogen compounds;extra protons can provide H^(+)to the nitrogen compounds,which will flexibly transfer between the nitrogen compound and active sites,thus improving the cleavage of the C-N bond.
基金National Natural Science Foundation of China(20406012) and CNPC program(04A5050102 and 05E7019).
文摘The kinetics of Athabasca bitumen derived heavy gas oil over NiMo/Al2O3 catalysts were studied in a JQ-II high-pressure microscale hydrotreator unit under different operation conditions, including temperature, pressure, H/O ratio and LHSV. The multi-parameter models of hydrodesulfurization and hydrodenitrogenation were proposed. The model parameters verify that the HDS and HDN reactions follow 1.5-order and 1.6-order kinetic rules, respectively. The kinetic activation energies of HDN and HDS over Com, Hom1 and Hom2 show that homemade catalysts exhibit higher activities in HDN than commercial catalyst. Using the multi-parameter kinetic model to predict the contents of sulfur and nitrogen in products is in good agreement with the experimental data.
文摘The catalysts were prepared by the temperature programmed reaction (TPR) of MoO3 with NH3 at various temperatures in the range of 573K~973K, and their hydrodenitrogenation (HDN) activities were tested in situ.It is shown that molybdenum nitrid(Mo2N) was formed above 923K and its intermediate MoO2 formed at about 573~623K under the rapid (5K/min.) TPR conditions.Mo2N is the most active species for pyridine HDN among MoO3,MoO2,MoS2,and Mo2N. Moreover,it can be promoted by adding Ni component.It is shown that the Ni/Mo2N catalyst prepared by adding some NiO into the precursor MoO3 has a steady HDN activity Which is far higher than that of the commercial sulfided NiMo/Al2O3(HR346) catalyst.