基于氧空位调变的稀土烧绿石型催化剂及其碳烟微粒催化燃烧性能研究

项目名称： 基于氧空位调变的稀土烧绿石型催化剂及其碳烟微粒催化燃烧性能研究

项目编号： No.21277059

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 环境科学、安全科学

项目作者： 王仲鹏

作者单位： 济南大学

项目金额： 80万元

中文摘要： 本项目基于柴油车尾气污染尚未根本解决这一问题而申请，利用我国丰富的稀土资源，开发低成本、高功效的稀土烧绿石A2B2O7型复合氧化物催化剂，使碳烟在排气温度下催化氧化去除，实现颗粒过滤器的原位再生。利用A2B2O7组成及性能的可控性，通过制备方法的选择，实现A位(La,Ce,Nd)和B位(Sn,Mn,Fe,Co,Cu)元素的同晶取代及微量贵金属的掺杂，以调变氧空位的类型和浓度，进而改变活性氧的浓度和移动性，形成氧化还原协同和酸碱协同作用，从内因(活性组元)和外因(催化剂与碳烟接触)两方面提高催化剂活性。采用拉曼技术表征氧空位浓度变化，结合碳烟厌氧滴定研究活性氧物种浓度及迁移规律，借助原位技术研究反映中间物种的转化规律，明确氧空位浓度、活性中心结构、氧化还原性与催化活性之间的关系；揭示碳烟在A2B2O7上催化燃烧的反应机制，为设计新一代柴油车碳烟燃烧催化剂提供科学依据。

中文关键词： 烧绿石；氧空位；碳烟颗粒物；催化燃烧；转化频率

英文摘要： This proposal is based on the prevention of diesel engine emission which is an important source of particulate matters in the air. Soot particulate is one of the main pollutants in diesel engine emissions causing serious problems to global environment and human health.Filtration and controllable regeneration within the exhaust stream are among the most promising methods for diesel soot removal, while the key technology of controllable regeneration is oxidation catalysis. Thus the goal of this study is to develop a new kind of lowcost and highly efficient rear-earth pyrocholres(A2B2O7) composite oxides for catalytic combustion of diesel soot particulate and to interpret the catalytic mechanisms.Due to the controllability of compositions and performances of pyrochlores, oxygen vacancies in A2B2O7 can be modulated through different preparation methods, isomorphous replacements of A site(by La, Ce, Nd) and/or B sites (by Sn, Mn and Fe, Co, Cu), and doping with trace amount of noble metal as well. Thereby, both the concentration and mobility of reactive oxygen species can be changed; redox and acid/basic synergistic effects can be also formed. The catalyst activity will be improved from the internal (active elements) side and extrinsic (catalyst and soot contact) side. In this study, the oxygen vacancy is characteriz

英文关键词： pyrochlore；oxygen vacancy；soot particulates；catalytic combustion；turnover frequency