Superior Performance of Fe1-xWxO delta for the Selective Catalytic Reduction of NOx with NH3: Interaction between Fe and W
发表时间：2019-03-12
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- 论文类型：
- 期刊论文
- 第一作者：
- Wang, Hui
- 通讯作者：
- Qu, ZP (reprint author), Dalian Univ Technol, Sch Environm Sci & Technol, Key Lab Ind Ecol & Environm Engn MOE, Linggong Rd 2, Dalian 116024, Peoples R China.
- 合写作者：
- Qu, Zhenping,Dong, Shicheng,Xie, Hongbin,Tang, Chen
- 发表时间：
- 2016-12-20
- 发表刊物：
- ENVIRONMENTAL SCIENCE & TECHNOLOGY
- 收录刊物：
- SCIE、EI、PubMed、PKU、ISTIC、Scopus
- 文献类型：
- J
- 卷号：
- 50
- 期号：
- 24
- 页面范围：
- 13511-13519
- ISSN号：
- 0013-936X
- 摘要：
- Novel iron-tungsten catalysts were first developed for the selective catalytic reduction of NOx by NH3 in diesel exhaust, achieving an excellent performance with a wide operating temperature window above 90% NOx conversion from 225 or 250 to 450 degrees C (GHSVs of 30 000 or 50 000 h(-1)). It also exhibited a pronounced stability and relatively high NOx conversion in the presence of H2O, SO2 and CO2. The introduction of W resulted in the formation of alpha-Fe2O3 and FeWO4 species obtained by HRTEM directly. The synergic effect of two species contributed to the high SCR activity, because of the increased surface acidity and electronic property. The FeWO4 with octahedral [FeO6]/[WO6] structure acted as the Bronsted acid sites to form highly active NH4+ species. Combining DFT calculations with XPS and UV-vis results, it was found that the fine electron interaction between alpha-Fe2O3 and FeWO4 made the electron more easily transfer from W6+ sites to Fe3+ sites, which promoted the formation of NO2. Judging by the kinetics and SCR activity studies, the Fe0.75W0.25O delta with an appropriate W amount showed the strongest interaction, and thereby the lowest activation energy of 39 kJ.mol(-1) and optimal catalytic activity. These findings would be conducive to the reasonable design of NH3-SCR catalysts by adjusting the fabrication.
- 是否译文：
- 否
