The CoMo/Al2O3 catalysts with different metal loading were studied by low temperature in situ FT-IR using CO as probe molecule which appears to be a powerful method by giving rise to signals specific for unpromoted an...The CoMo/Al2O3 catalysts with different metal loading were studied by low temperature in situ FT-IR using CO as probe molecule which appears to be a powerful method by giving rise to signals specific for unpromoted and promoted Mo sites.The result revealed that the increase of CoMoS phase on the catalyst surface improves the HDS activity and selectivity.The ratio of active site number of CoMoS and MoS_2 correlates linearly with HDS selectivity,which provides an effective tool for developing industrial selective HDS catalysts.展开更多
A series of CoMo/Al2O3 catalysts for selective hydrodesulfurization （HDS） of gasoline were studied with Raman spectroscopy, a powerful method that creates specific signals for the states and the distributions of oxi...A series of CoMo/Al2O3 catalysts for selective hydrodesulfurization （HDS） of gasoline were studied with Raman spectroscopy, a powerful method that creates specific signals for the states and the distributions of oxidic precursors and sulfided active phases. The higher the Mo and Co, the lower the tetrahedrally coordinated molybdate, and the higher the polymolybdate. But the amount of polymolybdate decreased when CoMoO4 appeared. Cobalt-promoted polymolybdate was the precursor, and its relative content correlated well with the HDS selectivity. For sulfided catalysts, adding the cobalt-promoter led to local distortion-disorder of the MoS2 structure and the formation of a CoMoS phase. This method can provide important information for designing new industrial selective-HDS catalvsts.展开更多
TiOz nanotubes （TiO2-NTs） were synthesized by the hydrothermal method. Co and Mo active components were supported on a series of the as-prepared TiO2-NTs samples which were calcined at different temperatures. The ef...TiOz nanotubes （TiO2-NTs） were synthesized by the hydrothermal method. Co and Mo active components were supported on a series of the as-prepared TiO2-NTs samples which were calcined at different temperatures. The effects of support calcination temperature of CoMo/TiOz- NTs catalysts on their catalytic performance were investigated for selective hydrodesulfurization （HDS）. The samples were characterized by means of the scanning electron microscopy （SEM）, the transmission electron microscopy （TEM）, N2 adsorption-desorption, X-ray diffraction （XRD）, Raman spectroscopy and H2 temperature-programmed reduction （Hz-TPR）. The experimental results revealed that TiOz-NTs support calcined under 500℃ can maintain the nanotubular structure with higher surface area and pore volume. Meanwhile, the obtained supported CoMo/TiO2-NTs catalysts exhibited weak metal-support interaction, more octahedral Mo6＋ species and high catalytic performance in selective HDS.展开更多
基金the founding of the State Key Project(Nos2006CB202506 and 2007BAE43B01)the State Key Laboratory of Catalytic Material and Reaction Engineering(RIPP,SINOPEC)
文摘The CoMo/Al2O3 catalysts with different metal loading were studied by low temperature in situ FT-IR using CO as probe molecule which appears to be a powerful method by giving rise to signals specific for unpromoted and promoted Mo sites.The result revealed that the increase of CoMoS phase on the catalyst surface improves the HDS activity and selectivity.The ratio of active site number of CoMoS and MoS_2 correlates linearly with HDS selectivity,which provides an effective tool for developing industrial selective HDS catalysts.
基金funding of the State Key Project (Nos. 2012CB224802 and 2012BAE05B03)the SINOPEC Project (No. 111015)
文摘A series of CoMo/Al2O3 catalysts for selective hydrodesulfurization （HDS） of gasoline were studied with Raman spectroscopy, a powerful method that creates specific signals for the states and the distributions of oxidic precursors and sulfided active phases. The higher the Mo and Co, the lower the tetrahedrally coordinated molybdate, and the higher the polymolybdate. But the amount of polymolybdate decreased when CoMoO4 appeared. Cobalt-promoted polymolybdate was the precursor, and its relative content correlated well with the HDS selectivity. For sulfided catalysts, adding the cobalt-promoter led to local distortion-disorder of the MoS2 structure and the formation of a CoMoS phase. This method can provide important information for designing new industrial selective-HDS catalvsts.
文摘TiOz nanotubes （TiO2-NTs） were synthesized by the hydrothermal method. Co and Mo active components were supported on a series of the as-prepared TiO2-NTs samples which were calcined at different temperatures. The effects of support calcination temperature of CoMo/TiOz- NTs catalysts on their catalytic performance were investigated for selective hydrodesulfurization （HDS）. The samples were characterized by means of the scanning electron microscopy （SEM）, the transmission electron microscopy （TEM）, N2 adsorption-desorption, X-ray diffraction （XRD）, Raman spectroscopy and H2 temperature-programmed reduction （Hz-TPR）. The experimental results revealed that TiOz-NTs support calcined under 500℃ can maintain the nanotubular structure with higher surface area and pore volume. Meanwhile, the obtained supported CoMo/TiO2-NTs catalysts exhibited weak metal-support interaction, more octahedral Mo6＋ species and high catalytic performance in selective HDS.
