Fan Xing, Kang Sijing, Li Jian, Zhu Tianle
Key Laboratory of Beijing on Regional Air Pollution Control, College of Environmental and Energy Engineering, Beijing University of Technology Beijing 100124 China
School of Space and Environment, Beihang University Beijing 100191 China.
RSC Adv. 2018 Jul 30;8(47):26998-27007. doi: 10.1039/c8ra05607b. eCollection 2018 Jul 24.
A coaxial dielectric barrier discharge (DBD) reactor has been developed for plasma and plasma-catalytic conversion of dilute NO in N and N-O mixtures at both room and high temperature (300 °C). The effects of catalyst introduction, O content and inlet NO concentration on NO conversion and the mechanism involved in the conversion of NO have been investigated. The results show that NO in N could be effectively decomposed to N and O by plasma and plasma-catalytic processes at both room and high temperature, with much higher decomposition efficiency at 300 °C than at room temperature for the same discharge power. Under an N-O atmosphere, however, NO could be removed only at high temperature, producing not only N and O but also NO and NO. Production and conversion of NO occur simultaneously during the plasma and plasma-catalytic processing of NO in a N-O mixture, with production and conversion being the dominant processes at room and high temperature, respectively. NO conversion increases with the increase of discharge power and decreases with the increase of O content. Increasing the inlet NO concentration from 100 to 400 ppm decreases the conversion of NO under an N atmosphere but increases that under an N-O atmosphere. Concentrating NO in the N-O mixture could alleviate the negative influence of O by increasing the involvement of plasma reactive species (, N(AΣ ) and O(D)) in NO conversion. Packing the discharge zone with a RuO/AlO catalyst significantly enhances the conversion of NO and improves the selectivity of NO decomposition under an N-O atmosphere, revealing the synergy of plasma and catalyst in promoting NO conversion, especially its decomposition to N and O.
已开发出一种同轴介质阻挡放电（DBD）反应器，用于在室温和高温（300°C）下对氮气和氮 - 氧混合物中的稀一氧化氮进行等离子体及等离子体催化转化。研究了引入催化剂、氧气含量和入口一氧化氮浓度对一氧化氮转化率的影响以及一氧化氮转化过程中涉及的机理。结果表明，在室温和高温下，氮气中的一氧化氮可通过等离子体和等离子体催化过程有效地分解为氮气和氧气，在相同放电功率下，300°C时的分解效率远高于室温。然而，在氮 - 氧气氛下，一氧化氮仅在高温下才能被去除，产物不仅有氮气和氧气，还有一氧化二氮和二氧化氮。在氮 - 氧混合物中对一氧化氮进行等离子体和等离子体催化处理时，一氧化二氮的生成和转化同时发生，在室温和高温下分别以生成和转化为主导过程。一氧化氮转化率随放电功率的增加而增加，随氧气含量的增加而降低。将入口一氧化氮浓度从100 ppm增加到400 ppm会降低氮气气氛下一氧化氮的转化率，但会增加氮 - 氧气氛下的转化率。在氮 - 氧混合物中浓缩一氧化氮可通过增加等离子体活性物种（电子、N(AΣ)和O(D)）参与一氧化氮转化来减轻氧气的负面影响。在放电区填充RuO/Al2O3催化剂可显著提高一氧化氮的转化率，并改善氮 - 氧气氛下一氧化氮分解的选择性，揭示了等离子体和催化剂在促进一氧化氮转化，特别是其分解为氮气和氧气方面的协同作用。
