物理化学学报 >> 2007, Vol. 23 >> Issue (09): 1425-1431.doi: 10.3866/PKU.WHXB20070922

研究论文 上一篇    下一篇

介质阻挡放电脱除甲醛的化学动力学模拟

张静; 吕福功; 徐勇; 杨学锋; 朱爱民   

  1. 大连理工大学三束材料改性国家重点实验室, 辽宁 大连 116024; 大连理工大学等离子体物理化学实验室, 辽宁 大连 116024
  • 收稿日期:2007-03-25 修回日期:2007-04-27 发布日期:2007-09-06
  • 通讯作者: 朱爱民 E-mail:amzhu@dlut.edu.cn

Chemical Kinetics of the Removal of Formaldehyde in Dielectric Barrier Discharges

ZHANG Jing; LU Fu-Gong; XU Yong; YANG Xue-Feng; ZHU Ai-Min   

  1. State Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Dalian University of Technology, Dalian 116024, Liaoning Province, P. R. China; Laboratory of Plasma Physical Chemistry, Dalian University of Technology, Dalian 116024, Liaoning Province, P. R. China
  • Received:2007-03-25 Revised:2007-04-27 Published:2007-09-06
  • Contact: ZHU Ai-Min E-mail:amzhu@dlut.edu.cn

摘要: 对大气压介质阻挡放电脱除甲醛进行了化学动力学模拟, 建立了时空平均化的模型, 并对相关的结果进行了实验验证. 分析了各主要物种的浓度随放电时间的变化, 在模拟空气气氛下, HCHO主要由O·和OH·自由基脱除, 其中, OH·自由基的作用更为突出. 强调了氮分子的第一电子激发态N2(A3∑+u)的作用, 它与O2、H2O 分子的碰撞增加了O·和OH·自由基的浓度,在氮气气氛中, N2(A3∑+u)态是使HCHO脱除的主要物种.讨论了HCHO初始浓度、气体流量对HCHO 脱除比能耗和产物中CO2/CO 摩尔比值的影响, HCHO 初始浓度较高时, 甲醛脱除的比能耗较低, 在输入能量密度<60 J·L-1, HCHO 初始浓度较低时, 产物中nCO2 /nCO值较高.

关键词: 介质阻挡放电, 甲醛, 化学动力学, 模型

Abstract: A time and space averaged chemical kinetics model in the removal of formaldehyde via a dielectric barrier discharge at atmospheric pressure and ambient temperature was reported. An analysis with regard to the discharge time evolution of the different main species was also included, and the results of the analysis showed that O· and OH·radicals, especially OH·radicals, were the key species for the removal of HCHO. The role played by the first electronically excited metastable state N2(A3∑+u) was clarified that, in air, the chemical attacks of O2 and H2Oby N2(A3∑+u) produced much more O·and OH·radicals. In nitrogen, N2(A3∑removal of HCHO. Specific energy cost and the molar ratio of nCO2 /nCO for HCHOremoval at different HCHOinitial concentrations and gas flow rates were also discussed. Specific energy cost at high HCHO initial concentration was lower than that at low HCHOinitial concentration. If input discharge energy density <60 J·L-1, nCO2 /nCO at lowHCHOinitial concentration was higher than that at high HCHO initial concentration.

Key words: Dielectric barrier discharge, HCHO, Chemical kinetics, Modeling