A novel material for passive NO_(x) adsorber:Ce-based BEA zeolite  

作　　者：Yan Wu Jun Wang Zexiang Chen Yi Zhu Minghui Yu Chen Wang Yanping Zhai Jianqiang Wang Gurong Shen Meiqing Shen 

机构地区：[1]School of Chemical Engineering and Technology,Tianjin University,Tianjin 300350,China [2]National Rare Earth Catalysis Research Institute,Dongying 257000,China [3]Department of Environmental Engineering and Technology,China Institute for Radiation Protection,Taiyuan 030006,China [4]School of Materials Science and Engineering,Tianjin University,Tianjin 300350,China [5]School of Environmental and Safety Engineering,North University of China,Taiyuan 030051,China [6]Collaborative Innovation Center of Chemical Science and Engineering(Tianjin),Tianjin 300350,China

出　　处：《Journal of Rare Earths》2023年第8期1163-1170,I0002,共9页稀土学报（英文版）

基　　金：supported by the National Key R&D Program of China(2021YFB3503200);the Major Science and Technology Programs of Yunnan Province(202002AB080001-1)。

摘　　要：Passive NO_(x) adsorbers(PNAs)were proposed to address the NO_(x) emissions during the cold start phase.Here we show a novel Ce-based BEA zeolite,as a noble-metal-free passive NO_(x)adsorber.The NO_(x) adsorption capacity of Ce/BEA reaches 36μmol/g in the feed gas close to realistic exhaust conditions,and the NO_(x) desorption temperature,which is around 290℃,is ideal for diesel exhaust after-treatment systems.Ce/BEA also behaves notable stability of high temperature CO exposure conditions.Multiple characterizations were performed to explore the NO_(x) adsorption chemistry of Ce/BEA.The Ce(Ⅳ)species in the BEA zeolite serves as the active center for NO_(x) adsorption.The bidentate nitrate species is responsible for the observed NO_(x) storage capacity,and the active oxygen around Ce(Ⅳ)plays a critical role in its formation.Considering the significantly better cost efficiency of Ce compared to Pd,Ce/BEA presents an enormous potential for the PNA applications and provides a novel formulation for the noblemetal choice of PNA materials.

关 键 词：Passive NO_(x)adsorbers Ce/BEA Non-noble-metal Cold start Rare earths 

分 类 号：TQ424.25[化学工程] X701[环境科学与工程—环境工程]