Effect of Water Vapor on the Selective Reduction of NO by Methane over Cobalt-Exchanged ZSM-5
Effect of Water Vapor on the Selective Reduction of NO by Methane over Cobalt-Exchanged ZSM-5
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DOI：
10.1006/jcat.1993.1231
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发表时间：
1993-08
影响因子：
7.3
通讯作者：
Yuejin. Li;P. J. Battavio;J. Armor
中科院分区：
文献类型：
--
作者：
Yuejin. Li;P. J. Battavio;J. Armor
研究了水蒸气对Co-ZSM-5催化剂上CH[sub 4]还原NO反应的影响。2%水的存在显著降低了T [le] 450[degree]C时的NO转化率，但在T [ge] 500[degree]C时影响较小。在低温下，水的存在增强了甲烷还原NO的选择性，而在高温下则没有变化。这种抑制在从系统中消除水后是可逆的。水的影响取决于所加入的水的水平、空速、反应温度和进料中甲烷的水平。水的添加将相对于CH[sub 4]或NO的经验反应级数从分数级增加到一级。程序升温脱附研究表明，未完全干燥的Co-ZSM-5对NO的吸附量显著降低，水对NO的吸附抑制可能是由于H2 O与NO的竞争吸附所致.此外，Co-ZSM-5能够同时去除干或湿进料中的NO和CO。参考文献25篇，图12，2个标签。
The effect of water vapor on the reduction of NO with CH[sub 4] in excess O[sub 2] over a Co-ZSM-5 catalyst was studied. The presence of 2% water significantly decreases the NO conversion at T [le] 450[degrees]C but has less of an effect at T [ge] 500[degrees]C. The selectivity of methane toward NO reduction was enhanced by the presence of water at low temperatures and is unchanged at high temperatures. This inhibition is reversible upon eliminating water from the system. The effect of water is dependent on the level of water added, space velocity, reaction temperature, and level of methane in the feed. The addition of water increases the empirical reaction order with respect to either CH[sub 4] or NO from a fractional order to first order. Temperature-programmed desorption studies show that the amount of NO adsorption on Co-ZSM-5 is significantly reduced if it is not fully dried, and the competitive adsorption between H[sub 2]O and NO is probably the cause of the inhibition by water. In addition, Co-ZSM-5 is capable of removing NO and CO simultaneously in either a dry or wet feed. 25 refs., 12 figs., 2 tabs.