A series of heteropoly acid (HPA) based Al2O3 catalysts with three-dimensional ordered (3DOM) structure were synthesized by colloidal crystal template method.Interconnected macropores (250 nm) could be clearly observe...A series of heteropoly acid (HPA) based Al2O3 catalysts with three-dimensional ordered (3DOM) structure were synthesized by colloidal crystal template method.Interconnected macropores (250 nm) could be clearly observed by scanning electron microscope (SEM) and transmission electron microscope (TEM).Mesopores could be detected by N2 adsorption-desorption isotherms which further confirmed the 3DOM structural characteristics of catalyst.Moreover,Keggin-type HPW was highly dispersed in the Al2O3 framework,which suggested by powder X-ray diffraction (XRD) and Fourier transform infrared spectra (FT-IR) results.The oxidation desulfurization (ODS) performance of 3DOM H3PW12O40/Al2O3 of refractory sulphur compounds was evaluated in the presence of hydrogen peroxide.It oxidized 98.5% of dibenzothiophene (DBT) into corresponding sulfone within 3 h,which exhibited superior ODS performance than corresponding mesoporous and microporous H3PW12O40/Al2O3 catalyst.The enhancement of ODS efficiency is related to the improvement of mass transfer of DBT in the pore channel resulting from the interconnected 3DOM structure.Furthermore,the as-prepared catalyst still demonstrates outstanding cycle performance after 6 runs,which could be easily recovered from the model fuel.展开更多
The gas-phase dehydration of glycerol was conducted over HPW/MCM-41 catalysts,which were prepared by impregnation of different amount of H3PW（12）O（40）（HPW）on the MCM-41 support.The samples were characterized by ...The gas-phase dehydration of glycerol was conducted over HPW/MCM-41 catalysts,which were prepared by impregnation of different amount of H3PW（12）O（40）（HPW）on the MCM-41 support.The samples were characterized by XRD,N2 physisorption,FTIR,NH3-TPD,and pyridine-FTIR measurements.N2 physisorption results suggested that the uniform framework of MCM-41 could still be well maintained after modified with HPW.Pyridine-FTIR experiments indicate that HPW modified MCM-41 can generate rich Br？nsted acid sites.Moreover,Brnsted acid sites facilitated to improve acrolein selectivity.Under the optimized reaction conditions：40wt%HPW loading,20%glycerol concentration,and 320℃reaction temperature,the glycerol conversion and acrolein selectivity reach 85%and 80%,respectively.展开更多
A nanosolid heteropoly acid of H 3PW 12 O 40 /SiO 2 was prepared with the sol-gel method and used to catalyze sythesis of methyl 5-amino-1,2,4,-trazolylformate sulfate.The structure of the nanosolid heteropoly acid H ...A nanosolid heteropoly acid of H 3PW 12 O 40 /SiO 2 was prepared with the sol-gel method and used to catalyze sythesis of methyl 5-amino-1,2,4,-trazolylformate sulfate.The structure of the nanosolid heteropoly acid H 3PW 12 O 40 /SiO 2 was characterized by IR,XRD and TEM.The following optimum condition were that the mole ratio of alcohol to carboxylic acid is 27∶1,the temperature is 75℃,the reaction time is 5 hours,and the catalyst is 2 5% of feedstock.Under the optimum conditions,the yield of esters was above 94%.展开更多
基金Funded by the National Natural Science Foundation of China(No.21476177)。
文摘A series of heteropoly acid (HPA) based Al2O3 catalysts with three-dimensional ordered (3DOM) structure were synthesized by colloidal crystal template method.Interconnected macropores (250 nm) could be clearly observed by scanning electron microscope (SEM) and transmission electron microscope (TEM).Mesopores could be detected by N2 adsorption-desorption isotherms which further confirmed the 3DOM structural characteristics of catalyst.Moreover,Keggin-type HPW was highly dispersed in the Al2O3 framework,which suggested by powder X-ray diffraction (XRD) and Fourier transform infrared spectra (FT-IR) results.The oxidation desulfurization (ODS) performance of 3DOM H3PW12O40/Al2O3 of refractory sulphur compounds was evaluated in the presence of hydrogen peroxide.It oxidized 98.5% of dibenzothiophene (DBT) into corresponding sulfone within 3 h,which exhibited superior ODS performance than corresponding mesoporous and microporous H3PW12O40/Al2O3 catalyst.The enhancement of ODS efficiency is related to the improvement of mass transfer of DBT in the pore channel resulting from the interconnected 3DOM structure.Furthermore,the as-prepared catalyst still demonstrates outstanding cycle performance after 6 runs,which could be easily recovered from the model fuel.
基金Funded by the National Natural Science Foundation of China(No.21303154)
文摘The gas-phase dehydration of glycerol was conducted over HPW/MCM-41 catalysts,which were prepared by impregnation of different amount of H3PW（12）O（40）（HPW）on the MCM-41 support.The samples were characterized by XRD,N2 physisorption,FTIR,NH3-TPD,and pyridine-FTIR measurements.N2 physisorption results suggested that the uniform framework of MCM-41 could still be well maintained after modified with HPW.Pyridine-FTIR experiments indicate that HPW modified MCM-41 can generate rich Br？nsted acid sites.Moreover,Brnsted acid sites facilitated to improve acrolein selectivity.Under the optimized reaction conditions：40wt%HPW loading,20%glycerol concentration,and 320℃reaction temperature,the glycerol conversion and acrolein selectivity reach 85%and 80%,respectively.
基金supported by the National Key Basic Research Program of China(973)(2010CB226903)National Natural Science Foundation of China(21073147,21303140)Program for Changjiang Scholars and Innovative Research Team in University,China(IRT1036)~~
文摘A nanosolid heteropoly acid of H 3PW 12 O 40 /SiO 2 was prepared with the sol-gel method and used to catalyze sythesis of methyl 5-amino-1,2,4,-trazolylformate sulfate.The structure of the nanosolid heteropoly acid H 3PW 12 O 40 /SiO 2 was characterized by IR,XRD and TEM.The following optimum condition were that the mole ratio of alcohol to carboxylic acid is 27∶1,the temperature is 75℃,the reaction time is 5 hours,and the catalyst is 2 5% of feedstock.Under the optimum conditions,the yield of esters was above 94%.
