催化学报

催化学报 ›› 2010, Vol. 31 ›› Issue (7): 817-821.

• 研究论文 • 上一篇    下一篇

介质阻挡放电与 CuZSM-5 结合方式对脱除 NOx 的影响

陈刚 1 , 孙琪 1, 2, 石雷 1, 牛金海 2, 宋志民 2   

  1. 1 辽宁师范大学化学化工学院, 辽宁大连 116029 2 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:2010-07-25 出版日期:2010-07-25 发布日期:2010-07-25

Effect of Combination Way of Dielectric Barrier Discharge and CuZSM-5 on NOx Removal

CHEN Gang1, SUN Qi1,2,*, SHI Lei1, NIU Jinhai2, SONG Zhimin2   

  1. 1School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, Liaoning, China 2Laboratory of Plasma Physical Chemistry, Dalian University of Technology, Dalian 116024, Liaoning, China
  • Received:2010-07-25 Online:2010-07-25 Published:2010-07-25

PDF

907

被引次数

14

摘要： 研究了介质阻挡放电 (DBD) 与 CuZSM-5 结合方式, 即 DBD 和 CuZSM-5 两段分置 (两段法) 或将 CuZSM-5 放入 DBD 区 (一段法), 对脱除氮氧化物的影响. 结果表明, 在 NO/N2 或 NO/C2H4/N2 无氧体系中, DBD 与 CuZSM-5 结合产生的协同效应很小; 在 NO/O2/N2 富氧体系中, DBD 与 CuZSM-5 结合导致氮氧化物转化率下降; 而在 NO/C2H4/O2 /N2 富氧体系中, 在 250 ºC, 空速 12 000 h?1, 输入放电能量密度 (Ein) 155 J/L 的条件下, 单纯催化、单纯等离子体放电、一段法和两段法时氮氧化物转化率分别为 39%, 1.5%, 79% 和 52%. 两段法产生了中等程度的协同效应, 主要是第一段等离子体放电产生新稳态物种 (如 NO2, CO 和 CO2 等) 起作用; 而一段法产生的协同效应较大, 主要是由于等离子体放电产生的新稳态物种和激发态短寿命物种 (如 N2*, NO*, CH 和 CN 等) 共同起作用.

关键词: 氮氧化物, 介质阻挡放电, 发射光谱, 协同效应, 铜, ZSM-5 分子筛

Abstract: The effect of the combination way of dielectric barrier discharge (DBD) stage filled with fused silica pellets and a CuZSM-5 catalyst on NOx removal was investigated by one-stage plasma-over-catalyst (POC) and two-stage plasma-followed-by-catalyst (PFC) reactors. In the NO/N2 or NO/C2H4/N2 system, there was a small synergistic effect between DBD plasmas and CuZSM-5 using the one-stage POC and the two-stage PFC reactors. The NOx conversion from the one-stage POC reactor or the two-stage PFC reactor decreased in the NO/O2/N2 system. Under the conditions of the reaction mixture of NO, C2H4, O2, and N2, gas hourly space velocity of 12 000 h–1, the input discharge energy density (Ein) of 155 J/L, and 250 ºC, the NOx conversions in the systems of pure catalyst, pure plasma, plasma-catalyst combination in a one-stage POC reactor, and a two-stage PFC reactor were 39%, 1.5%, 79%, and 52%, respectively. The observed moderately plasma-enhanced NOx conversion in the two-stage reactor was attributed to the stable species such as NO2, CO, and CO2 formed in its first discharge stage. Both short-lived active species (such as N2*, NO*, CH, and CN) and stable species formed from the plasma-induced or plasma-catalytic process in the one-stage reactor may be responsible for the significant synergistic effect between the DBD plasmas and CuZSM-5 catalyst.

Key words: nitrogen oxide;dielectric barrier discharge, emission spectroscopy;synergistic effect;copper;ZSM-5 zeolite