摘要
为了研究低温等离子体（NTP）对NOx储存还原（NSR）催化剂吸附储存性能的促进作用,设计了一套以石英玻璃为介质的介质阻挡放电反应器,以NO/O2/N2模拟稀燃发动机尾气,结合自制催化剂,在不同温度和不同NTP、催化剂结合方式的情况下进行了程序升温脱附（TPD）实验。实验研究表明：NTP的引入,可以有效延长催化剂的吸附饱和时间;催化剂位于NTP中时,对NOx的储存能力明显得到增强,比位于NTP之后效果更好;由于NTP的协同作用,催化剂的脱附峰向低温区移动;吸附温度为100～300℃,NTP对催化剂的吸附储存均有促进作用,且在较低温度下更为明显。
In order to study the storage capability of NSR catalyst improved by nonthermal plasma, a dielectric barri er discharge （DBI） reactor using quartz glass as its dielectric medium was designed. The experimental apparatus included this DBD reactor, ac high voltage power source （high frequency or power frequency） , gas control system, catalytic reactor, NOx analyzer, oven and temperature controller. The simulated exhaust gas was prepared by mix ing N2 gas, O2 gas and a small amount of concentrated NO gas （5.0%, balanced with N2 ）. The usual NSR catalyst without Pt （20%BaO/Al2O3 ） was used in our experiment. The catalyst was either placed in the NTP reactor, or in a U-shaped quartz glass after the NTP reactor. The experiment called temperature programmed desorption （TPD） was utilized to study the catalyst token in NOx adsorption under different temperatures. The experimental results show that when NTP is introduced in catalyst reactor, the saturation time of adsorption is extended efficiently. When catalyst is placed in the NTP reactor, the NOx storage capability is enhanced obviously, and it is much better than that when the catalyst is placed after the NTP reactor. Subject to the restriction of catalyst＇s own storage capacity, high frequency NTP which provides more energy injection cannot raise the total amount of adsorption further more, compared with the power frequency NTP. Cooperated with NTP, the desorption peak of the NSR catalyst moves towards low temperature area, which indicates a better low temperature characteristic of NOx adsorption. From 100 ℃ to 300 ℃, with the assistance of NTP, the improvement of catalyst adsorption capability is observed, which is more significant at lower temperatures.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2008年第10期2145-2149,共5页
High Voltage Engineering
基金
国家自然科学基金(20507012)~~
