Regeneration mechanism of Pd/AC catalyst in dielectric barrier discharge plasma

doi:10.3969/j.issn.0438-1157.2013.01.033

Abstract

Abstract: Regeneration of deactivated Pd/AC catalyst was carried out in a dielectric barrier discharge (DBD) plasma reactor and activities of regenerated catalysts were assessed by catalytic ozonation reactions.The surface morphology,surface area and organic compounds were characterized by SEM,BET and TG respectively.In order to investigate regeneration mechanism of Pd/AC catalyst,concentration of O₃ and plasma emission spectra during DBD process were detected.The results showed that regeneration efficiency could be by 95% after 30 min treatment.Nitrobenzene degradation efficiency was 87% using ozonation reaction catalyzed by Pd/AC catalyst regenerated under the optimized condition.The regeneration efficiency with ozone solely was only 25.6%,indicating that radicals with strong oxidation ability produced in DBD process was main factor for Pd/AC catalyst regeneration.

Key words: Pd/AC catalyst, dielectric barrier discharge, catalyst regeneration, free radicals

摘要： 利用介质阻挡放电对失活钯炭催化剂(Pd/AC)进行再生,并通过催化臭氧氧化硝基苯反应评价再生后催化剂的活性。运用扫描电镜(SEM)、比表面积测定(BET)、热重分析(TG)等测定手段对Pd/AC进行表征;并对放电过程进行臭氧产量测定和等离子体发射光谱诊断,分析了Pd/AC催化剂再生的机理。结果表明,催化剂经放电处理30 min后再生率为95%;利用在最优条件下再生的Pd/AC进行催化臭氧氧化反应,硝基苯的降解率为87%;再生过程中臭氧贡献率仅为25.6%,表明放电过程中产生的强氧化性自由基是促使催化剂再生的主要因素。

关键词: Pd/AC催化剂, 介质阻挡放电, 催化剂再生, 自由基

CLC Number:

TQ426.81

GAO Wenli, WANG Xiao, LI Zhongjian, ZHANG Xingwang, YU Qingni, LEI Lecheng. Regeneration mechanism of Pd/AC catalyst in dielectric barrier discharge plasma[J]. CIESC Journal, 2013, 64(1): 297-302.

高文立, 王骁, 李中坚, 张兴旺, 余青霓, 雷乐成. 介质阻挡放电技术再生Pd/AC催化剂的机理探讨[J]. 化工学报, 2013, 64(1): 297-302.

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