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| Degradation properties and mechanism of naphthalene from exhaust gas using dielectric barrier discharge |
| WU Zu-liang1, XIE De-yuan1, LU Hao1, YAO Shui-liang1, GAO Xiang2 |
| 1. College of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, China; 2. State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China |
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Abstract Effects of the initial volume fraction of naphthalene, residence time and exhaust gas components on naphthalene degradation process were analyzed. The naphthalene degradation mechanism was explored through byproducts analysis. Degradation efficiency decreases with the increasing initial volume fraction, while the energy utilization efficiency improves. When the residence time is prolonged, the degradation efficiency trends to be stable, while the COx selection rate enhances step by step. The degradation efficiency can reach above 70% as the volume fraction of oxygen gas from exhausted gas is 3%, but the COx selection rate is only 30%. The degradation efficiency is relatively stable when the volume fraction of oxygen gas is 3%-20%, while the COx selection rate gradually increases and goes to 77% at 20% volume fraction of oxygen gas. According to the degradation byproducts, nitrogen gas excited state plays an important role during the initial degradation of naphthalene. And O radical can promote the naphthalene degradation through some direct collision reactions. However, complete degradation of naphthalene depends on O and OH radicals.
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Published: 01 April 2015
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介质阻挡放电废气中萘的降解特性和机理
针对大气中日益严重的多环芳烃（PAHS）污染问题，采用介质阻挡放电对模拟废气中萘的降解特性和机理进行了研究,分析萘的初始体积分数、停留时间和废气组分对萘降解效率和降解产物的影响,并通过对降解副产物的分析，探索其降解机理.研究结果表明：萘初始体积分数的增加引起了萘降解效率下降,但提高了降解的能量利用率；随着反应停留时间的延长,萘的降解效率趋于平稳,COx选择率逐步提高；当废气中氧气的体积分数为3%时,70%以上的萘能被降解,但COx选择率却只有30%；当氧气体积分数为3%～20%时,萘的降解效率相对稳定,但COx选择率却稳步提高；当氧气体积分数为20%时，COx选择率达到77%.根据降解副产物的分析,氮气激发态在萘的初始降解过程中起到重要的作用,而且O自由基能够通过与萘分子的直接碰撞反应促进萘的降解，而萘的深度降解则依靠O、OH等自由基的氧化.
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| ［1］ ZHANG Y X, TAO S, SHEN H Z, et al. Inhalation exposure to ambient polycyclic aromatic hydrocarbons and lung cancer risk of Chinese population［J］. Proceedings of the National Academy of the Sciences of the United States of America, 2009, 106(50): 21063-21067.
［2］ ZHANG Y X, TAO S. Global atmospheric emission inventory of polycyclic aromatic hydrocrbons (PAHs) for 2004［J］. Atmospheric Environment, 2009, 43(4): 812-819.
［3］ ZHU L Z, LU H, CHEN S G, et al. Pollution level, phase distribution and source analysis of polycyclic aromatic hydrocarbons in residential air in Hangzhou, China［J］. Journal of Hazardous Materials, 2009, 162（2/3）:1165-1170.
［4］ YANG K, ZHU L Z, XING B S. Adsorption of polycyclic aromatic hydrocarbons by carbon nanomaterials［J］. Environmental Science & Technology, 2006, 40(6): 1855-1861.
［5］ SHEMER H, LINDEN K G. Photolysis, oxidation and subsequent toxicity of a mixture of polycyclic aromatic hydrocarbons in natural waters［J］. Journal of Photochemistry and Photobiology A, 2007, 187: 186-195.
［6］ BEKBOLET M, CMAR Z, KILIC M, et al. Photocatalytic oxidation of dinitronaphthalenes: theory and experiment［J］. Chemosphere, 2009, 75（8）: 1008-1014.
［7］ ZENG Y, HONG P K A, WAVREK D A. Integrated chemical-biological treatment of benzo［a］pyrene［J］. Environmental Science & Technology, 2000, 34: 854-862.
［8］ EL-ALAWI Y. Measurement of short- and long-term toxicity of polycyclic aromatic hydrocarbons using luminescent bacteria Ecotoxicol［J］. Environmental Safety, 2002, 51: 12-21.
［9］ KIM H H. Nonthermal plasma processing for air-pollution control: a historical review, current issues, and future prospects［J］. Plasma Processes and Polymers, 2004, 1: 91-110.
［10］ DURME J V, DEWULF J, LEYS C, et al. Combining non-thermal plasma with heterogeneous catalysis in waste gas treatment: a review［J］. Applied Catalysis B: Environmental, 2008, 78(3/4): 324-333.
［11］ CHEN H L, LEE H M, CHEN S H, et al. Removal of volatile organic compounds by single-stage and two-stage plasma catalysis systems: a review of the performance enhancement mechanisms, current status, and suitable applications［J］. Environmental Science & Technology, 2009, 43(7): 2216-2227.
［12］ YE Z, ZHANG Y, LI P, et al. Feasibility of destruction of gaseous benzene with dielectric barrier discharge［J］. Journal of Hazardous Material, 2008, 90(1/2): 356-364.
［13］ BLIN-SIMIAND N, JORAND F, MAGNE L,et al. Plasma reactivity and plasma-surface interactions during treatment of toluene by a dielectric barrier discharge［J］. Plasma Chemistry and Plasma Processing, 2008, 28(4): 429-466.
［14］ KRAWEZYK K, ULEJCZYK B, SONG H K, et al. Plasma-catalytic reactor for decomposition of chlorinated hydrocarbons［J］. Plasma Chemistry and Plasma Processing, 2009, 29(1): 27-41.
［15］ MOK Y S, DEMIDYUK V,WHITEHEAD J C. Decomposition of hydrofluorocarbons in a dielectric-packed plasma reactor［J］. Journal of Physical Chemistry A, 2008, 112(29): 6586-6591.
［16］ OSTAPCZUK A, HAKODA T, SHIMADA A, et al. Naphthalene and acenaphthene decomposition by electron beam generated plasma application［J］. Plasma Chemistry and Plasma Processing, 2009, 28(4): 483-494.
［17］ YU L, LI X, TU X, et al. Decomposition of naphthalene by dc gliding arc gas discharge［J］. Journal of Physical Chemistry A, 2010, 114(1): 360-368.
［18］ ABDELAZIZ A A, SETO T, ABDEL-SALAM M, et al. Performance of a surface dielectric barrier discharge based reactor for destruction of naphthalene in an air stream［J］. Journal of Physics D: Applied Physics, 2012, 45(11): 110.
［19］ HARLING A M, GLOVER D J, WHITEHEAD J C, et al. The role of ozone in the plasma-catalytic destruction of environmental pollutants［J］. Applied Catalysis B: Environmental, 2009, 90(1/2): 157-161.
［20］ YU L, LI X D, TU X, et al. Decomposition of Naphthalene by dc Gliding Arc Gas Discharge［J］. Journal of Physical Chemistry A, 2010, 114: 360-368.
［21］ SIMIAND N B, JORAND F, MAGNE L, et al. Plasma reactivity and plasma-surface interactions during treatment of toluene by a dielectric barrier discharge［J］. Plasma Chemistry and Plasma Processing, 2008, 28(4): 429-466. |
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