气体再燃低NOx燃烧中NO与NHi的反应机理研究

杜梅芳; 张影; 樊俊杰; 吴高贺; 侯宁普; 鲁贵林; 张忠孝

气体再燃低NO_x燃烧中NO与NH_i的反应机理研究

上海理工大学, 上海 200093

基金项目: 国家自然科学基金(50906055)。

详细信息

通讯作者:
张忠孝, E-mail: zhzhx222@163.com.

中图分类号: O641
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- 文章访问数: 1951
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- 被引次数: 0
出版历程
- 收稿日期: 2011-11-04
- 修回日期: 2012-01-27
- 刊出日期: 2012-08-31

Research on reaction mechanism between NO and NH_i during low NO_x gas reburning

University of Shanghai for Science and Technology, Shanghai 200093, China

摘要

摘要: 采用量子化学密度泛函理论(DFT)对NO与NH_i自由基的反应机理进行了研究,并结合经典过渡态理论对各反应速率常数进行了计算。结果表明,NO与NH₂自由基的反应体系可通过六个反应通道形成N₂+H₂O、N₂O+H₂和N₂H+OH。从能量变化和反应速率两方面考虑,产物N₂+H₂O最容易生成,其最佳反应通道为NO+NH₂→→N₂+H₂O;NO与NH自由基的反应体系可通过七个反应通道形成N₂+OH、N₂O+H和N₂H+O;其中,N₂+OH最容易生成,最佳反应通道为NO+NH→→N₂+OH。比较发现, NH比NH₂自由基更易与NO发生反应生成N₂。因此,在实际运行中改变操作条件,实现NH₂等向NH方向转化,有利于NO_x的还原。
- NO /
- NH_i自由基 /
- 密度泛函理论(DFT) /
- 反应速率
Abstract: The reaction mechanisms between free radicals NO and NH_i were studied using quantum chemical density functional theory (DFT) and rate constant for each reaction was calculated combining with classical transition state theory in this paper. The results show that there are six different reaction channels for free radicals NO and NH₂, and the products are N₂+H₂O, N₂O+H₂ and N₂H+OH. The optimum reaction channel is NO+NH₂→→N₂+H₂O from the views of energy change and reaction rate. Similarly, N₂+OH, N₂O+H and N₂H+O will be produced by seven different reaction channels between free radicals NO and NH, and the optimum reaction channel is NO+NH→→N₂+OH. So it is easier for free radical NH reacting with NO to generate N₂ than NH₂. Therefore, an important conclusion was got that the lower NO_x emission could be obtained by making NH₂ turn to NH in the actual operation.
- NO /
- free radical NH_i /
- density functional theory (DFT) /
- reaction rate

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