Alkali- and Sulfur-Resistant Tungsten-Based Catalysts for NOx Emissions Control

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• 作者：Zhiwei Huang ; Hao Li ; Jiayi Gao ; Xiao Gu ; Li Zheng ; Pingping Hu ; Ying Xin ; Junxiao Chen ; Yaxin Chen ; Zhaoliang Zhang ; Jianmin Chen ; Xingfu Tang
• 刊名：Environmental Science & Technology
• 出版年：2015
• 出版时间：December 15, 2015
• 年：2015
• 卷：49
• 期：24
• 页码：14460-14465
• 全文大小：371K
• ISSN：1520-5851

文摘

The development of catalysts with simultaneous resistance to alkalis and sulfur poisoning is of great importance for efficiently controlling NO_x emissions using the selective catalytic reduction of NO_x with NH₃ (SCR), because the conventional V₂O₅/WO₃鈥揟iO₂ catalysts often suffer severe deactivation by alkalis. Here, we support V₂O₅ on a hexagonal WO₃ (HWO) to develop a V₂O₅/HWO catalyst, which has exceptional resistance to alkali and sulfur poisoning in the SCR reactions. A 350 渭mol g^鈥? K⁺ loading and the presence of 1,300 mg m^鈥? SO₂ do not almost influence the SCR activity of the V₂O₅/HWO catalyst, and under the same conditions, the conventional V₂O₅/WO₃鈥揟iO₂ catalysts completely lost the SCR activity within 4 h. The strong resistance to alkali and sulfur poisoning of the V₂O₅/HWO catalysts mainly originates from the hexagonal structure of the HWO. The HWO allows the V₂O₅ to be highly dispersed on the external surfaces for catalyzing the SCR reactions and has the relatively smooth surfaces and the size-suitable tunnels specifically for alkalis鈥?diffusion and trapping. This work provides a useful strategy to develop SCR catalysts with exceptional resistance to alkali and sulfur poisoning for controlling NO_x emissions from the stationary source and the mobile source.