MO_(δ)/3 DOM ZSM-5催化剂的制备及同时消除炭烟和NO_(x)的催化性能  

Preparation of MO_(δ)/3 DOM ZSM-5 Catalysts and Their Catalytic Performance for the Simultaneous Removal of Soot and NO_(x)

作　　者：王斓懿 王世伟 陈心宇 于迪 张春雷 范晓强 于学华 赵震 WANG Lanyi;WANG Shiwei;CHEN Xinyu;YU Di;ZHANG Chunlei;FAN Xiaoqiang;YU Xuehua;ZHAO Zhen(Institute of Catalysis for Energy and Environment,College of Chemistry and Chemical Engineering,Shenyang Normal University,Shenyang 110034,China;State Key Laboratory of Heavy Oil Processing,China University of Petroleum,Beijing 102249,China)

机构地区：[1]沈阳师范大学化学化工学院,能源与环境催化研究所,沈阳110034 [2]中国石油大学(北京)重质油国家重点实验室,北京102249

出　　处：《高等学校化学学报》2025年第2期103-118,共16页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:22402129,22072095,22372107);国家重点研发计划项目(批准号:2022YFB3506200,2022YFB3504100);辽宁省教育厅高等学校基本科研项目(批准号:LJ202410166024);辽宁省研究生教育教学改革研究资助项目(批准号:LNYJG2023280,LNYJG2022400);辽宁省优秀青年科学基金(批准号:2022-YQ-20);辽宁省兴辽英才计划项目(批准号:XLYC2203007,XLYC2203138);沈阳师范大学博士启动基金(批准号:BS202416)资助.

摘　　要：炭烟颗粒和NO_(x)作为柴油机尾气的主要污染物严重危害了人体健康与环境.因此,炭烟与NO_(x)的催化净化得到了广泛关注.本文设计制备了具有独特孔结构的三维有序大孔(3DOM)ZSM-5分子筛催化剂,并将其作为载体,制备了一系列3DOM ZSM-5担载MO_(δ)(M=Mn,Fe,Co,Ce,Pr,W)的催化剂.所制备催化剂均具有独特的多级孔结构,有利于炭烟与NO_(x)等小分子的捕捉与传质,可进一步增强催化剂的催化性能.其中,MnO_(δ)/3DOM ZSM-5催化剂具有最佳的同时消除炭烟与NO_(x)的催化性能,其炭烟燃烧的峰值温度最低(453℃),80%以上NO转化率的初始温度最低(184℃)且温度窗口较宽(184~362℃).该催化剂优异的催化性能与其良好的氧化还原性能、丰富的酸位点、充足的活性氧以及丰富的多级孔结构有关.动力学测试结果表明,MnO_(δ)/3DOM ZSM-5催化剂具有最高的本征活性.根据催化剂的活性测试和原位漫反射红外光谱(in situ DRIFTS)结果,推断了该催化剂在不同温度下的反应机理.在低温(<300℃)条件下,反应以脱硝为主,主要遵循Eley-Rideal(E-R)机理;在高温条件下(>300℃)主要以炭烟燃烧为主,包括活性氧机理和NO_(2)辅助机理.Soot particles and NO_(x),as the main pollutants in diesel engine exhaust,have caused a serious threat to people's health and the surrounding environment.Therefore,the catalytic purification of soot and NO_(x) is of wide concern.In this work,the three-dimensionally ordered macroporous(3 DOM)ZSM-5 zeolite catalyst with unique pore structures was prepared and taken as a carrier.The 3 DOM ZSM-5 supported MO_(δ)(M=Mn,Fe,Co,Ce,Pr,W)cata⁃lysts were also prepared.The prepared catalysts have a unique hierarchical pore structure,which is conducive to the capture and mass transfer of soot and small molecules such as NO x,thereby enhancing the catalytic performance of the catalysts.Among the prepared catalysts,MnO_(δ)/3 DOM ZSM-5 catalyst exhibits the best catalytic performance for the simultaneous removal of soot and NO x,and its peak temperature for soot combustion is the lowest(453℃),the initial temperature for NO conversion above 80%is the lowest(184℃)and the temperature window(184-362℃)over 80%NO conversion is wider.The excellent catalytic performance of MnO_(δ)/3 DOM ZSM-5 is related to the good redox ability,abundant acid sites,sufficient reactive oxygen species,and rich hierarchical pore structures.Meanwhile,MnO_(δ)/3 DOM ZSM-5 catalyst also has the highest intrinsic activity according to the kinetic test results.In addition,based on the results of the activity test and in situ diffuse reflectance infrared spectroscopy(in situ DRIFTS),the reaction mechanisms of the catalyst at different temperatures were proposed.At low temperatures(<300℃),the reaction mainly belongs to denitrification,following the Eley-Rideal(E-R)mechanism.Soot combustion mainly occurs at high temperatures(>300℃),including activated oxygen mechanism and NO_(2) assisted mechanism.

关 键 词：MO_(δ)/3DOM ZSM-5催化剂 炭烟燃烧 NO_(x)去除 反应机理 

分 类 号：O643.36[理学—物理化学] X701[理学—化学]