联合发射光谱与动力学计算的非热等离子体重整CO_(2)-CH_(4)机理  

Mechanism exploration of non-thermal plasma reforming of CO_(2)-CH_(4)by combining emission spectroscopy and kinetics calculations

作　　者：陈玉民[1] 卢钱程 雷文涛 岳文静 张兵[1] 黄文捷 赵永椿[2] 张军营[2] CHEN Yumin;LU Qiancheng;LEI Wentao;YUE Wenjing;ZHANG Bing;HUANG Wenjie;ZHAO Yongchun;ZHANG Junying(School of Low-Carbon Energy and Power Engineering,China University of Mining and Technology,Xuzhou 221116,China;State Key Laboratory of Coal Combustion,Huazhong University of Science and Technology,Wuhan 430074,China)

机构地区：[1]中国矿业大学低碳能源与动力工程学院,江苏徐州221116 [2]华中科技大学煤燃烧国家重点实验室,湖北武汉430074

出　　处：《洁净煤技术》2022年第10期54-67,共14页Clean Coal Technology

基　　金：国家自然科学基金资助项目(51606216,52176144);中央高校基本科研业务费专项资金资助项目(2020ZDPYMS23);国家重大科研仪器研制资助项目(51827808)。

摘　　要：非平衡等离子体重整CO_(2)-CH_(4)制合成气是实现2种温室气体资源化利用的新兴技术途径。综合采用发射光谱分析、反应动力学计算和连续质谱对常温常压介质阻挡放电(DBD)非热等离子体重整CO_(2)-CH_(4)反应途径进行探索。比功率S EI为52 J/cm^(3)时,可得到CH_(4)和CO_(2)转化率最大分别为22.8%和9.4%。稳态气相产物连续质谱在线分析表明,C_(2)H_(4)为C_(2)烃生成重要中间体,CH_(4)比例越高C_(2)烃生成量越大,且按C_(2)H_(6)<C_(2)H_(4)<C_(2)H_(2)顺序升高。发射光谱检测到·CH、·C_(2)自由基和CO、CO_(2)^(+)特征谱线,·CH相对强度随比功率增加明显降低,CO_(2)^(+)相对强度变化较小。通过动力学计算分析C_(2)和C_(3)产物生成消耗途径,发现89.2%C_(2)H_(6)来自复合反应CH_(3)+CH_(3)(+M)C_(2)H_(6)(+M),78.9%C_(2)H_(4)主要由CH_(4)+CHC_(2)H_(4)+H和C_(2)H_(3)+H(+M)C_(2)H_(4)(+M)反应生成,61.1%C_(2)H_(2)受电子碰撞反应影响形成,C_(2)产物形成遵循路径:CH_(4)→C_(2)H_(6)→C_(2)H_(4)→C_(2)H_(2)。电子碰撞离解CO_(2)反应e+CO_(2)CO+O^(-)是CO重要形成途径,而CH_(3)+CH_(4)C_(2)H_(5)^(+)+H_(2)反应和电子碰撞解离CH_(4)是H_(2)关键生成路径。研究表明,动力学模拟结合发射光谱可为合理揭示DBD重整CO_(2)-CH_(4)过程复杂反应机理提供有力工具。CO_(2)-CH_(4) reforming by non-equilibrium plasma to syngas is an important emerging technology pathway to realize the resource utilization for the two greenhouse gases.The reaction pathway of CO_(2)-CH_(4) reforming by non-thermal plasma in a dielectric barrier discharge(DBD)reactor at ambient temperature and pressure was thoroughly investigated by combing emission spectrometry analysis,reaction kinetics simulation and continuous mass spectrometry measurements.A maximum conversion of CH_(4)and CO_(2)of 25.8%and 9.6%respectively,can be achieved under a specific energy input(S EI)of 52 J/cm^(3).The continuous mass spectrometry online analysis of the stable gaseous products shows that C_(2)H_(4)acts as a key intermediate in the formation of C_(2) hydrocarbons.The higher the proportion of CH_(4),the greater the generation of C_(2)hydrocarbons,and it increases in the order of C_(2)H_(6)<C_(2)H_(4)<C_(2)H_(2).·CH,·C_(2)radicals and characteristic spectral lines of CO and CO_(2)^(+) are detected in the emission spectrum.The relative intensity of·CH decreases significantly with the increase of specific power,and the relative intensity of CO_(2)^(+) changes little.The generation and consumption pathways of C_(2)and C_(3)products are analyzed by kinetic calculation,and it is found that 89.2%of C_(2)H_(6)comes from the combination reaction CH_(3)+CH_(3)(+M)→C_(2)H_(6),78.9%of C_(2)H_(4)is mainly formed by CH_(4)+CH→C_(2)H_(4)+H and C_(2)H_(3)+H(+M)→C_(2)H_(4)(+M)reaction,61.1%of C_(2)H_(2)is formed by electron collision reaction,and the formation of C_(2)product follows the path:CH_(4)→C_(2)H_(6)→C_(2)H_(4)→C_(2)H_(2).The reaction of electron collision dissociation e+CO_(2)CO+O^(-)of CO_(2)is an important formation pathway of CO,while the reaction CH_(3)+CH_(4)→C_(2)H_(5)^(+) H_(2)and electron collision dissociation of CH_(4)are the key generation pathway of H_(2).Integration of emission spectroscopy and kinetic calculation provides a useful tool to uncover the reaction mechanism of plasma-enhanced CO_(2)-

关 键 词：非热等离子体 CO_(2)-CH_(4)重整 发射光谱 反应机理 化学动力学模型 等离子体化学 

分 类 号：TQ53[化学工程—煤化学工程] TK114[动力工程及工程热物理—热能工程]