Ce-promoted Mn/ZSM-5 catalysts for highly efficient decomposition of ozone

作     者：Linlin Wei Hongxia Chen Ying Wei Jingbo Jia Runduo Zhang Linlin Wei;Hongxia Chen;Ying Wei;Jingbo Jia;Runduo Zhang

作者机构：State Key Laboratory of Chemical Resource EngineeringBeijing Key Laboratory of Energy Environmental CatalysisBeijing University of Chemical TechnologyBeijing 100029PR China 

出 版 物：《Journal of Environmental Sciences》 (环境科学学报（英文版）)

年 卷 期：2021年第33卷第5期

页      面：219-228页

核心收录：

学科分类：081705[工学-工业催化] 07[理学] 08[工学] 0817[工学-化学工程与技术] 070602[理学-大气物理学与大气环境] 080502[工学-材料学] 0706[理学-大气科学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：financially supported by the National Natural Science Foundation of China(Nos.U1862102,21976012) the Fundamental Research Funds for the Central Universities(XK1802-1,JD2016) 

主　　题：Manganese oxide ZSM-5 zeolite Ce promoter Adsorbed oxygen Ozone decomposition 

摘      要：Manganese oxides supported by ZSM-5 zeolite(Mn/ZSM-5) as well as their further modified by Ce promoter were achieved by simple impregnation method for ozone catalytic decomposition. The yCe20Mn/ZSM-5–81 catalyst with 8% Ce loading showed the highest catalytic activity at relative humidity of 50% and a space velocity of 360 L/(g × hr), giving 93% conversion of 600 ppm O_(3) after 5 hr. Moreover, this sample still maintained highly activity and stability in humid air with 50%–70% relative humidity. Series of physicochemical characterization including X-ray diffraction, temperature-programmed technology(NH_3-TPD and H_(2)-TPR), X-ray photoelectron spectroscopy and oxygen isotopic exchange were introduced to disclose the structure-performance relationship. The results indicated that moderate Si/Al ratio(81) of zeolite support was beneficial for ozone decomposition owing to the synergies of acidity and hydrophobicity. Furthermore, compared with 20 Mn/ZSM-5-81, Ce doping could enhance the amount of low valance manganese(such as Mn^(2+) and Mn^(3+)). Besides, the Ce^(3+)/Ce^(4+) ratio of 8Ce20Mn/ZSM-5-81 sample was higher than that of 4Ce_(2)0 Mn/ZSM-5-81. Additionally, the synergy between the MnO_x and CeO_(2) could easily transfer electron via the redox cycle, thus resulting in an increased reducibility at low temperatures and high concentration of surface oxygen. This study provides important insights to the utilization of porous zeolite with high surface area to disperse active component of manganese for ozone decomposition.