HCN oxidation in an O2/CO2 atmosphere: An experimental and kinetic modeling study
HCN oxidation in an O2/CO2 atmosphere: An experimental and kinetic modeling study
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DOI：
10.1016/j.combustflame.2009.07.016
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发表时间：
2010-02-01
影响因子：
4.4
通讯作者：
Alzueta, M. U.
中科院分区：
文献类型：
--
作者：
Gimenez-Lopez, J.;Millera, A.;Alzueta, M. U.
HCN 是 NOx 化学（包括形成和去除过程）中最重要的中间体之一，因此了解 HCN 氧化对于最大限度地减少 NOx 排放非常重要。目前的工作旨在评估 HCN 在 O-2/CO2 气氛中的氧化行为，因为缺乏对这些特定操作条件的研究，并且以 O-2/CO2 燃烧气氛而不是空气为特征的氧燃料燃烧过程的重要性日益增加。为此，我们对 CO2 稀释条件下、900-1450 K 温度范围和不同化学计量（从极还原条件到氧化条件）下的 HCN 氧化进行了流动反应器实验和动力学模型研究。与传统的空气燃烧相比，在 O-2/CO2 气氛中观察到的巨大实验差异证实了 O-2/CO2 环境中 HCN 氧化研究的重要性。高浓度 CO2 的存在明显抑制 HCN 氧化，因为 CO2 通过 CO2 + H 可逆箭头 CO + OH 反应与 O-2 竞争原子氢。实验结果显示了不同化学计量下 HCN 的氧化状态，分析了该过程主要产物的形成：CO、NO、N-2、N2O 和 HNCO。尽管反应起始温度在所研究的任何化学计量中几乎相似，但较高的氧气利用率会增加 HCN 转化率。用于计算的机制是由 Dagaut 等人开发的。 [P。 Dagaut，P.格拉尔堡，M.U.阿尔苏埃塔，Prog。能量燃烧。科学。 34 (2008) 1-46]关于HCN在空气燃烧中的氧化，在当前工作中更新以考虑O-2/CO2燃烧气氛的存在。一般来说，修改后的模型对所进行的实验给出了相当好的描述。 (C) 2009 年燃烧研究所。由爱思唯尔公司出版。保留所有权利。
HCN is one of the most important intermediates in NOx chemistry including formation and removal processes and the knowledge of HCN oxidation is thus very important to minimize NOx emissions. The present work aims to evaluate the oxidation behavior of HCN in an O-2/CO2 atmosphere, due to the lack of studies at these specific operating conditions and the increasing importance of the oxy-fuel combustion processes, characterized by an O-2/CO2 combustion atmosphere instead of air. With this purpose, a flow reactor experimental and kinetic modeling study of the oxidation of HCN under CO2 diluted conditions, in the 900-1450 K temperature range and for different stoichiometries, ranging from very reducing to oxidizing conditions, has been performed. The large experimental differences observed in the O-2/CO2 atmosphere in comparison to traditional air-fired combustion corroborate the importance of the HCN oxidation study in an O-2/CO2 environment. The presence of high CO2 concentration levels clearly inhibits HCN oxidation, since CO2 competes With O-2 for atomic hydrogen through the CO2 + H reversible arrow CO + OH reaction. The experimental results show the oxidation regime of HCN for different stoichiometries, analyzing the formation of the main products of the process: CO, NO, N-2, N2O and HNCO. The higher availability of oxygen increases the HCN conversion, even though the onset temperature for reaction is almost similar at any stoichiometry studied. The mechanism used for calculations was that developed by Dagaut et al. [P. Dagaut, P. Glarborg, M.U. Alzueta, Prog. Energy Combust. Sci. 34 (2008) 1-46] for the oxidation of HCN in air combustion, updated in the present work to take into account the presence of an O-2/CO2 combustion atmosphere. In general, the modified model gives a reasonably good description of the experiments performed. (C) 2009 The Combustion Institute. Published by Elsevier Inc. All rights reserved.