催化学报

催化学报 ›› 2010, Vol. 31 ›› Issue (1): 56-60.

• 研究论文 • 上一篇    下一篇

NO 和 NO2 在 V2O5/AC 催化剂表面的反应行为

孙德魁1,2, 刘振宇1,3, 贵国庆1, 黄张根1, 刘清雅3, 肖勇1   

  1. 1 中国科学院山西煤炭化学研究所煤转化国家重点实验室, 山西太原030001 2 中国科学院研究生院, 北京100049 3 北京化工大学化工资源有效利用国家重点实验室, 北京100029
  • 收稿日期:2010-01-25 出版日期:2010-01-25 发布日期:2010-01-25

Reaction of NO and NO2 with NH3 over V2O5/AC Catalyst

SUN Dekui1,2, LIU Zhenyu1,3,*, GUI Guoqing1, HUANG Zhanggen1, LIU Qingya3, XIAO Yong 1   

  1. 1State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, Shanxi, China 2Graduate University of Chinese Academy of Sciences, Beijing 100049, China 3State Key Laboratory of Chemical Resources Engineering, Beijing University of Chemical Technology, Beijing 100029, China
  • Received:2010-01-25 Online:2010-01-25 Published:2010-01-25

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1391

被引次数

28

摘要： 采用程序升温脱附、在线质谱和原位漫反射红外光谱等手段, 比较了 NO 和 NO2 在 V2O5 及 V2O5/AC 催化剂表面的选择催化还原 (SCR) 反应行为. 结果表明, 氨以质子态 NH4+和共价态 NH3 分子两种形态吸附于纯 V2O5 表面, V=O 为氨的主要吸附活性位. 无氧状态下, NO 和 NO2 皆可与吸附于 V2O5 表面的 NH3 反应, 并且 NO2 与吸附态 NH3 的反应活性高于 NO. 但在 V2O5/AC 催化剂表面, 同样在无氧条件下, NO 几乎不与吸附态 NH3 反应, 而 NO2 却可以反应并生成 N2. 在 V2O5/AC 表面, NO 很容易被气相 O2 氧化为 NO2, 然后参与 SCR 反应. 可见, NO2 是 NO 在 V2O5/AC 表面发生 SCR 反应的中间体.

关键词: 五氧化二钒, 活性炭, 氮氧化物, 氨, 选择性催化还原

Abstract: Temperature-programmed desorption, on-line mass spectroscopy, and in situ diffuse reflectance infrared Fourier transform spectroscopy were preformed to study selective catalytic reduction (SCR) of NO and NO2 with NH3 over V2O5 and activated carbon (AC)-supported V2O5 (V2O5/AC). The results show that both protonated (NH4+) and molecularly coordinated (NH3) ammonia species form on the V2O5 surface and V=O bond is the primary active site. Both NO2 and NO can react with the adsorbed ammonia in the absence of oxygen, but the activity of NO2 is superior to that of NO. On the V2O5/AC surface, NO2 still can react with the adsorbed NH3 species to form N2, but NO shows little activity unless oxygen is present. SCR of NO on V2O5/AC proceeds through oxidation of NO to NO2 by oxygen on the AC surface followed by reaction of NO2 with NH3 species adsorbed and activated on the V2O5 surface.

Key words: vanadium oxide, activated coke, nitrogen oxide, ammonia, selective catalytic reduction