Effects of WOx modification on the activity, adsorption and redox properties of CeO_2 catalyst for NO_x reduction with ammonia

查看全文 作　　者：Ziran [1]Ma;Duan [1]Weng;Xiaodong [1,2]Wu;Zhichun [3]Si

机构地区：[1]State Key Laboratory of New Ceramics&Fine Process,Department of Materials Science and Engineering,Tsinghua University,Beijing 100084,China;[2]Yangtze Delta Region Institute of Tsinghua University,Zhejiang 314000,China;[3]Advanced Materials Institute,Graduate School at Shenzhen,Tsinghua University,Shenzhen 518055,China

出　　处：《Journal of Environmental Sciences》索引2012年第24卷第7期,共12页

基　　金：the Ministry of Science and Technology, PR China for financial support of Project 2010CB732304;Science and Technology Department of Zhejiang Province Project 2011C31010 摘　　要：A series of WO3/CeO2 (WOx/CeO2) catalysts were synthesized by wet impregnation of ammonium metatungstate on a CeO2 support. The resulting solid acid catalysts were characterized by X-ray diffraction (XRD), UV-Vis spectroscopy (UV-Vis), Raman spectroscopy (Raman), in-situ Fourier transform infrared spectroscopy (in-situ FT-IR) of ammonia adsorption, NH3-TPD, H2 temperature-programmed reduction (H2-TPR), NH3/NO oxidation and activity measurements for NOx reduction by NH3 (NH3-SCR). The results show that polytungstate (WOx) species are the main species of tungsten oxide on the surface of ceria. The addition of tungsten oxide enhances the Bro¨nsted acidity of ceria catalysts remarkably and decreases the amount of surface oxygen on ceria, with strong interaction between CeO2 and WOx. As a result, the N2 selectivity of NH3 oxidation and NH3-SCR at high temperatures (> 300℃) is enhanced. Therefore, a wide working temperature window in which NOx conversion exceeds 80% (NOx conversion > 80%) from 200 to 450℃, is achieved over 10 wt.% WOx/CeO2 catalyst. A tentative model of the NH3-SCR reaction route on WOx/CeO2 catalysts is presented. 关键词：固体酸催化剂氧化还原性能 NOx还原 CEO2 活性测定 WOX 氨还原吸附

相关文献

参考文献（49）
引证文献（24）
耦合文献（52）

参考文献(49)

引证文献(24)

耦合文献(52)

互联网出版许可证新出网证(渝)字10号全国400电话 - 免长途话费

Effects of WOx modification on the activity, adsorption and redox properties of CeO_2 catalyst for NO_x reduction with ammonia

参考文献(49)

引证文献(24)

耦合文献(52)

用户提示