Removal of toluene by non-thermal plasma coupled with Cu-Ce catalysts

doi:10.16085/j.issn.1000-6613.2017-2042

Abstract

Abstract: The study investigated the removal of toluene via non-thermal plasma combined with Cu-Ce catalysts. The catalysts were prepared by the citric acid sol-gel method. Compared with the plasma-only process, the introduction of the Cu-Ce catalysts could greatly enhance the toluene removal efficiency. The toluene removal efficiency increased with the decrease of the initial concentration or the gas flow rate and with the increase of the voltage. The catalysts were characterized by BET, XRD, XPS, H₂-TPR and FTIR, respectively. The active components of the Cu-Ce catalysts distributed uniformly. The contents of oxygen vacancies and the adsorbed oxygen in the Cu-Ce catalysts were higher than those in the CuO or CeO₂ catalysts, which is beneficial to the release of active oxygen. There was synergistic effect between Cu and Ce, and the redox cycles between them could further promote the oxidation of toluene.

Key words: toluene, non-thermal plasma, Cu-Ce catalysts, oxygen vacancy

摘要： 以挥发性有机化合物（VOCs）中的代表物质甲苯作为脱除对象，采用柠檬酸水热法制得铜铈催化剂，考察了低温等离子体协同不同摩尔比铜铈催化剂脱除甲苯的性能。研究发现铜铈复合型金属催化剂可以大幅度提升低温等离子体对甲苯的脱除效率，降低初始浓度、气体流速和升高电压可以提高甲苯脱除效率。同时利用N₂吸附-脱附（BET）、X射线衍射（XRD）、X射线光电子能谱（XPS）、程序升温还原（H₂-TPR）、红外光谱（FTIR）等手段对催化剂进行表征，发现催化剂活性组分分布较均匀，铜铈复合型金属催化剂表面氧空位、吸附态氧含量高于单金属氧化物催化剂，这有利于催化剂活性氧的释放。铜铈之间存在着协同作用，铜铈之间的氧化还原循环有利于甲苯的氧化。

关键词: 甲苯, 低温等离子体, 铜铈催化剂, 氧空位

CLC Number:

X511

GAN Rongli, LUO Guangqian, XU Yang, MEI Ruidong, ZHU Hailu, ZHOU Mengli. Removal of toluene by non-thermal plasma coupled with Cu-Ce catalysts[J]. Chemical Industry and Engineering Progress, 2018, 37(09): 3416-3423.

甘蓉丽, 罗光前, 许洋, 梅瑞冬, 朱海露, 周梦丽. 低温等离子体协同铜铈催化剂脱除甲苯[J]. 化工进展, 2018, 37(09): 3416-3423.

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