Effects of different introduction methods of Ce⁴⁺ and Zr⁴⁺ on denitration performance and anti-K poisoning performance of V₂O₅-WO₃/TiO₂ catalyst

Jun Cao^1,2，Xiaojiang Yao^1,2，Li Chen¹，Keke Kang¹，Min Fu²，Yang Chen¹

1. Research Center for Atmospheric Environment,Key Laboratory of Reservoir Aquatic Environment of CAS,Chongqing Institute of Green and Intelligent Technology,Chinese Academy of Sciences2. Chongqing Key Laboratory of Catalysis and New Environmental Materials,College of Environment and Resources,Chongqing Technology and Business University

摘 要：The purpose of this work is to explore the effects of the introduction methods of Ce⁴⁺ and Zr⁴⁺on the physicochemical properties,activity,and K tolerance of V₂ O₅-WO₃/TiO₂ catalyst for the selective catalytic reduction of NO_x by NH₃.Four different methods,namely pre-impregnation,post-impregnation,coimpregnation,and co-precipitation,were used to synthesize a series of V₂ O₅-WO₃-TiO2-CeO₂-ZrO₂ catalysts.The catalysts were characterized by XRD,BET,NH₃-TPD,XPS,and H₂-TPR techniques.Moreover,the activity and anti-K poisoning performance were tested by an NH₃-SCR model reaction.The results show that the introduction of Ce⁴⁺ and Zr⁴⁺ can improve the catalytic performance of V₂O₅-WO₃/TiO₂ catalyst,but the impregnation method cannot enhance the anti-K poisoning performance.Ce⁴⁺ and Zr⁴⁺introduced by co-precipitation method can effectively improve the tolerance of K,which is mainly due to the incorporation of Ce⁴⁺ and Zr⁴⁺ into TiO₂ lattice to form a uniform TiO₂-CeO₂-ZrO₂ solid solution,resulting in the optimal surface acidity and redox performance,and reducing the decreases caused by Kpoisoning.Furthermore,based on the best introduction method,we further optimized the molar ratio of Ce⁴⁺/Zr⁴⁺,It is found that the catalyst exhibits the best anti-K poisoning performance when the molar ratio of Ce⁴⁺/Zr⁴⁺is 2:1.

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