介质阻挡放电脱除甲醛的化学动力学模拟  

Chemical Kinetics of the Removal of Formaldehyde in Dielectric Barrier Discharges

作　　者：张静 吕福功[1] 徐勇[2] 杨学锋[2] 朱爱民[2] 

机构地区：[1]大连理工大学等离子体物理化学实验室,辽宁大连116024 [2]大连理工大学三束材料改性国家重点实验室,辽宁大连116024

出　　处：《物理化学学报》2007年第9期1425-1431,共7页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金(50177003);教育部"新世纪优秀人才支持计划"(NCET-06-0282)资助

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N_2(A^3∑_u^+)的作用,它与O_2、H_2O分子的碰撞增加了O~·和OH~·自由基的浓度,在氮气气氛中,N_2(A^3∑_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CO_2/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n_(CO_2)/n_(CO)值较高.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（A^3∑u^＋）was clarified that,in air,the chemical attacks of O2 and H2O by N2（A^3∑u^＋） produced much more O^·and OH^·radicals.In nitrogen,N2（A^3∑u^＋）made a great contribution in the removal of HCHO. Specific energy cost and the molar ratio of n（CO2）/n（CO） for HCHO removal at different HCHO initial concentrations and gas flow rates were also discussed.Specific energy cost at high HCHO initial concentration was lower than that at low HCHO initial concentration.If input discharge energy density〈60 J·L^-1,n（CO2）/n（CO） at low HCHO initial concentration was higher than that at high HCHO initial concentration.

关 键 词：介质阻挡放电 甲醛 化学动力学 模型 

分 类 号：O643.1[理学—物理化学]