Effects of cerium and tungsten addition on acid-base properties of spindle-likeα-Fe_(2)O_(3)in low-temperature SCR of NO_(x)with NH_(3)  

作　　者：Jun Ni Xuanbei Peng Linlin Yang Kai Zhang Yangyu Zhang Yanliang Zhou Xiuyun Wang Chak-tong Au Lilong Jiang 

机构地区：[1]National Engineering Research Center of Chemical Fertilizer Catalyst,Fuzhou University,Fuzhou 350002,China

出　　处：《Journal of Rare Earths》2022年第11期1734-1742,I0003,共10页稀土学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(21703037,22108037);the Natural Science Foundation of Fujian(2018J10691)。

摘　　要：Low-temperature selective catalytic reduction(SCR)is important for the elimination of NOfrom stationary sources.In the present study,the loading of Ce and W onα-Fe_(2)O_(3)was achieved through the integration of single-mode microwave and incipient wetness impregnation(IWI)methods.The scanning electron microscopy(SEM)and transmission electron microscopy(TEM)images reveal that the structure ofα-Fe_(2)O_(3)is spindle-like,and the structure remains unchanged after the introduction of Ce and/or W.The results of NH-SCR investigation demonstrate that NOconversion over Ce-W/α-Fe_(2)O_(3)is more than85%at 300℃,which is much higher than that over Ce/a-Fe_(2)O_(3)andα-Fe_(2)O_(3),Our studies illustrate that the addition of Ce can significantly increase the amount of surface oxygen vacancies as well as sites of moderate basicity.On the other hand,the addition of W can obviously decrease the amount of basic sites and increase the number of Br?nsted acid sites.The synergistic effect of Ce and W addition on balancing acidity/basicity properties accounts for the high activity of CeW/α-Fe_(2)O_(3)for NOremoval at low temperatures.The study provides insight into the relationship between acidity/basicity properties and catalytic performance of Ce-W/α-Fe_(2)O_(3)catalysts,which is beneficial to the design of high-performance NH-SCR catalyst for NOremoval at low temperatures.

关 键 词：NH_(3)-SCR Fe_(2)O_(3) NO_(x)removal Acidity/basicity properties Morphology structure Rare earths 

分 类 号：TQ426[化学工程] X701[环境科学与工程—环境工程]