Ceria is widely used as a promoter in "three-way catalysts" (TWC). The promotion effect of ceria was originally supposed to be in the structural aspects and chemical ones. Precious metals are widely used for...Ceria is widely used as a promoter in "three-way catalysts" (TWC). The promotion effect of ceria was originally supposed to be in the structural aspects and chemical ones. Precious metals are widely used for exhaust gas emission control. However, because the high cost of precious metals and their sensitivity to sulfur poisoning, attention has been given to nonprecious metal catalysts such as copper oxide.展开更多
The catalytic activity of carbon nanotubes-supported vanadium oxide(V_2O_5/CNTs) catalysts in the selective catalytic reduction(SCR) of NO with NH_3 at low temperatures(<250℃) was investigated.The effects of V_2O_...The catalytic activity of carbon nanotubes-supported vanadium oxide(V_2O_5/CNTs) catalysts in the selective catalytic reduction(SCR) of NO with NH_3 at low temperatures(<250℃) was investigated.The effects of V_2O_5loading,reaction temperature,and presence of SO_2 on the SCR activity were evaluated.The results show that V_2O_5/CNTs catalysts exhibit high activity for NO reduction with NH_3 at low-temperatures.The catalysts also show very high stability in the presence of SO_2.More interestingly,their activities are significantly promoted instead of being poisoned by SO_2.The promoting effect of SO_2 is distinctly associated with V_2O_5 loading,particularly maximized at low V_2O_5 loading,which indicated the role of CNTs support in this effect.The promoting effect of SO_2 at low temperatures suggests that V_2O_5/CNTs catalysts are promising catalytic materials for low-temperature SCR reactions.展开更多
文摘Ceria is widely used as a promoter in "three-way catalysts" (TWC). The promotion effect of ceria was originally supposed to be in the structural aspects and chemical ones. Precious metals are widely used for exhaust gas emission control. However, because the high cost of precious metals and their sensitivity to sulfur poisoning, attention has been given to nonprecious metal catalysts such as copper oxide.
基金Supported by the National Natural Science Foundation of China(21006065)the Zhejiang Provincial Natural Science Foundation of China(Y5100009)
文摘The catalytic activity of carbon nanotubes-supported vanadium oxide(V_2O_5/CNTs) catalysts in the selective catalytic reduction(SCR) of NO with NH_3 at low temperatures(<250℃) was investigated.The effects of V_2O_5loading,reaction temperature,and presence of SO_2 on the SCR activity were evaluated.The results show that V_2O_5/CNTs catalysts exhibit high activity for NO reduction with NH_3 at low-temperatures.The catalysts also show very high stability in the presence of SO_2.More interestingly,their activities are significantly promoted instead of being poisoned by SO_2.The promoting effect of SO_2 is distinctly associated with V_2O_5 loading,particularly maximized at low V_2O_5 loading,which indicated the role of CNTs support in this effect.The promoting effect of SO_2 at low temperatures suggests that V_2O_5/CNTs catalysts are promising catalytic materials for low-temperature SCR reactions.
