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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 V2O5-WO3/TiO2 catalyst for the selective catalytic reduction of NOx by NH3. Four different methods, namely pre-impregnation, post-impregnation, co-impregnation, and co-precipitation, were used to synthesize a series of V2O5-WO3-TiO2-CeO2-ZrO2 cat-alysts. 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 K-poisoning. 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.