In this study,we prepared Fe_(2)O_(3)-Nb_(2)O_(5)binary mixed oxide catalysts using co-precipitation(CP),sol-gel(SG),and solid process(SR)methods and tested their performance.All the catalysts exhibited over 75%NO_(x)...In this study,we prepared Fe_(2)O_(3)-Nb_(2)O_(5)binary mixed oxide catalysts using co-precipitation(CP),sol-gel(SG),and solid process(SR)methods and tested their performance.All the catalysts exhibited over 75%NO_(x)removal efficiency between 250℃and 400℃.Compared with the samples prepared by the SR method,catalyst synthesized using CP and SG methods possessed a larger specific surface area,which could compensate for the lower surface area-normalized reaction rate originat-ing from the insufficient reactive surface oxygen species,hence exhibiting a relatively high low-temperature apparent deNO_(x)activity.However,at a high-temperature region,limited amount of reactive surface oxygen species,together with abundant strong acid sites,facilitated the proceeding of NH_(3)reduction of NO_(x),which well explained the higher apparent activity of the catalyst prepared by SG method than the other two samples.It seemed that specific surface area had an important role to play in the low-temperature apparent performance of the catalysts,while chemical properties mainly decided the activity at an elevated temperature.展开更多
文摘In this study,we prepared Fe_(2)O_(3)-Nb_(2)O_(5)binary mixed oxide catalysts using co-precipitation(CP),sol-gel(SG),and solid process(SR)methods and tested their performance.All the catalysts exhibited over 75%NO_(x)removal efficiency between 250℃and 400℃.Compared with the samples prepared by the SR method,catalyst synthesized using CP and SG methods possessed a larger specific surface area,which could compensate for the lower surface area-normalized reaction rate originat-ing from the insufficient reactive surface oxygen species,hence exhibiting a relatively high low-temperature apparent deNO_(x)activity.However,at a high-temperature region,limited amount of reactive surface oxygen species,together with abundant strong acid sites,facilitated the proceeding of NH_(3)reduction of NO_(x),which well explained the higher apparent activity of the catalyst prepared by SG method than the other two samples.It seemed that specific surface area had an important role to play in the low-temperature apparent performance of the catalysts,while chemical properties mainly decided the activity at an elevated temperature.
