The Pt-bearing SO42-/ZrO2 superacid catalysts supported on ultra stable Y (USY) zeolite were prepared by impregnation and characterized by X-ray diffracti on, nitrogen adsorption and Hammett indicators. Their catalyti...The Pt-bearing SO42-/ZrO2 superacid catalysts supported on ultra stable Y (USY) zeolite were prepared by impregnation and characterized by X-ray diffracti on, nitrogen adsorption and Hammett indicators. Their catalytic activities were evaluated in the hydroisomerization of n-heptane with an atmospheric fixed-bed r eactor. The catalysts possessed a high surface area, superacidity and well maint ained pore structure of USY support. The supported catalysts with a suitable SO4 2-/ZrO2 loading exhibited a higher catalytic activity and selectivity than the u nsupported SO42-/ZrO2 catalyst or the Pt supported on USY catalyst without super acid. At the reaction temperature of 220 ℃, over the catalyst with a Pt loading of 0.8wt% and ZrO2 loading of 10wt%, the conversion of n-heptane could be as hi gh as 35.2% with a selectivity of 87.9% for isomerization products.展开更多
The effective B acid amount of dealuminated USY(DUSY) zeolites with different silica/alumina ratios were measured by UV spectrometry with 2,6 dimethyl pyridine as adsorbentes in the presence of cyclohexane or anhydrou...The effective B acid amount of dealuminated USY(DUSY) zeolites with different silica/alumina ratios were measured by UV spectrometry with 2,6 dimethyl pyridine as adsorbentes in the presence of cyclohexane or anhydrous ethanol or tetrahydrofuran.The isomerization of α pinene was used to check the acidic catalytic properties of these zeolites.The results indicate that effective B acid amount of DUSY measured in polar anhydrous ethanol or tetrahydrofuran is lower than that of non polar cyclohexane.The effect of solution concentration of effective B acid amount of DUSY zeolites is small.As the silica/alumina ratio of catalyst increases,effective B acid amount and conversion of isomerization of α pinene all raise.展开更多
The reaction of αpinene isomerization catalyzed by dealuminated USY(DUSY,SiO2/Al2O3=861)in the solvents of different dielectric constant was studied.The effect of reaction time and temperature on conversion...The reaction of αpinene isomerization catalyzed by dealuminated USY(DUSY,SiO2/Al2O3=861)in the solvents of different dielectric constant was studied.The effect of reaction time and temperature on conversion and product distrbutions in the different solvents was investigated.The experimental result shows that the reaction of αpinene isomerization was favored in polar tetrahydrofuran with a larger dielectric constant.展开更多
文摘The Pt-bearing SO42-/ZrO2 superacid catalysts supported on ultra stable Y (USY) zeolite were prepared by impregnation and characterized by X-ray diffracti on, nitrogen adsorption and Hammett indicators. Their catalytic activities were evaluated in the hydroisomerization of n-heptane with an atmospheric fixed-bed r eactor. The catalysts possessed a high surface area, superacidity and well maint ained pore structure of USY support. The supported catalysts with a suitable SO4 2-/ZrO2 loading exhibited a higher catalytic activity and selectivity than the u nsupported SO42-/ZrO2 catalyst or the Pt supported on USY catalyst without super acid. At the reaction temperature of 220 ℃, over the catalyst with a Pt loading of 0.8wt% and ZrO2 loading of 10wt%, the conversion of n-heptane could be as hi gh as 35.2% with a selectivity of 87.9% for isomerization products.
文摘The effective B acid amount of dealuminated USY(DUSY) zeolites with different silica/alumina ratios were measured by UV spectrometry with 2,6 dimethyl pyridine as adsorbentes in the presence of cyclohexane or anhydrous ethanol or tetrahydrofuran.The isomerization of α pinene was used to check the acidic catalytic properties of these zeolites.The results indicate that effective B acid amount of DUSY measured in polar anhydrous ethanol or tetrahydrofuran is lower than that of non polar cyclohexane.The effect of solution concentration of effective B acid amount of DUSY zeolites is small.As the silica/alumina ratio of catalyst increases,effective B acid amount and conversion of isomerization of α pinene all raise.
文摘The reaction of αpinene isomerization catalyzed by dealuminated USY(DUSY,SiO2/Al2O3=861)in the solvents of different dielectric constant was studied.The effect of reaction time and temperature on conversion and product distrbutions in the different solvents was investigated.The experimental result shows that the reaction of αpinene isomerization was favored in polar tetrahydrofuran with a larger dielectric constant.
