Catalytic performance of Fe-ZSM-5 catalysts for selective catalytic reduction of nitric oxide by ammonia
Catalytic performance of Fe-ZSM-5 catalysts for selective catalytic reduction of nitric oxide by ammonia
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DOI：
10.1006/jcat.1999.2674
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发表时间：
1999-12-10
影响因子：
7.3
通讯作者：
Yang, RT
中科院分区：
文献类型：
--
作者：
Long, RQ;Yang, RT
研究了一系列铁交换分子筛作为氨选择性催化还原 (SCR) NO 的催化剂。结果发现，Fe-ZSM-5 和 Fe-丝光沸石催化剂对 SCR 反应具有很高的活性。在 400-500 摄氏度、高空速（GHSV = 4.6 x 10(5) l/h）条件下，获得了接近 100% 的 NO 转化率。然而，具有较大孔径的 Fe-Y 和 Fe-MCM-41 在该反应中表现出较低的活性。对于Fe-ZSM-5催化剂，SCR活性随着沸石中Si/Al比的增加而降低。随着 Fe-ZSM-5 催化剂中 Fe 交换水平从 58% 增加到 252%，NO 转化率在较低温度（例如 300 摄氏度）下增加，但在高温（例如 600 摄氏度）下下降。与商用氧化钒催化剂相比，基于一阶速率常数，Fe-ZSM-5催化剂在400℃时的活性高出五倍，在450℃时的活性高出七倍。它还在更宽的温度窗口中发挥作用，仅产生N-2（而不是N2O）和H2O，并且将SO2氧化成SO3的活性显着降低。 (C) 1999 年学术出版社。
A series of Fe-exchanged molecular sieves were studied as catalysts for the selective catalytic reduction (SCR) of NO with ammonia. It was found that Fe-ZSM-5 and Fe-mordenite catalysts were highly active for the SCR reaction. Nearly 100% NO conversions were obtained at 400-500 degrees C under conditions with a high space velocity (GHSV = 4.6 x 10(5) l/h). However, Fe-Y and Fe-MCM-41 with larger pore sizes showed lower activities for this reaction. For Fe-ZSM-5 catalysts, the SCR activity decreased with increasing Si/Al ratio in the zeolites. As the Fe-exchange level in the Fe-ZSM-5 catalysts was increased from 58 to 252%, NO conversion increased at lower temperatures (e.g., 300 degrees C), but decreased at high temperatures (e.g., 600 degrees C). Compared with the commercial vanadia catalyst, based on the first-order rate constants, the Fe-ZSM-5 catalyst was five times more active at 400 degrees C and seven times more active at 450 degrees C. It also functioned in a broader temperature window produced only N-2 (rather than N2O) and H2O, and showed a substantially lower activity for oxidation of SO2 to SO3. (C) 1999 Academic Press.