抗碱/碱土金属中毒的钛基核壳脱硝催化剂构筑及作用机理研究

项目名称： 抗碱/碱土金属中毒的钛基核壳脱硝催化剂构筑及作用机理研究

项目编号： No.51278458

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 建筑科学

项目作者： 吴忠标

作者单位： 浙江大学

项目金额： 80万元

中文摘要： 氮氧化物是烟气中的主要污染物之一，选择性催化还原法是国内外首选的脱硝技术。目前广泛使用的钒钛脱硝催化剂极易发生由碱金属和碱土金属导致的中毒，且这一失活现象在水泥厂、垃圾焚烧厂、生物质发电厂等碱性物质含量高的尾气治理中尤为严重。这已严重阻碍SCR技术的进一步推广和完善，并很可能影响我国氮氧化物控制的成效。目前国内外还缺乏能改善催化剂抗碱性金属中毒能力的有效办法，基于此，本研究提出以构筑钛基核壳催化剂的方法来提高脱硝催化剂对碱性金属的抗性。本研究将活性金属粒子负载入钛纳米管的管腔内部，借助钛纳米管的物理隔绝作用和化学捕集能力，阻碍碱性金属毒害活性金属粒子，从而有效提高催化剂的抗碱性金属中毒能力。通过提出和完善核壳催化剂的抗碱性中毒作用机制，明确核壳催化剂抗中毒能力的决定性因素，为催化剂抗中毒能力的进一步提升提供理论指导。本研究开发的催化剂具有优异的脱硝活性、稳定性、选择性和抗碱性金属中毒能力。

中文关键词： 选择性催化还原；钛纳米管；固体超强酸；过渡金属氧化物；抗碱金属中毒

英文摘要： NOx is one of the key air pollutants from flue gas, and selective catalytic reduction with NH3 was the most reliable method to reduce the emission of NOx from stationary sources. Although vanadia-based catalysts have been extensively employed in commercial SCR processes, the drawbacks associated with the alkaline poisoning still remain.The alkaline poisoning was even more serious in the bio-fuel plants, refuse incinerators and cement plants. Though the deactivation of deNOx catalysts has retarded the progress of the SCR technology and challenged the successful control of NOx emission, there still lacks of breakthroughs to improve the alkaline tolerance of deNOx catalysts. Aiming to develop deNOx catalysts with high resistance to alkaline poisoning, we propose a new solution by introducing the metal oxides into the tubular channels of titanate nanotubes. These core-shell catalysts can effectively shield the active phases from the poisons with the tubular channel of titanate nanotubes. Furthermore, the poisons may be arrested by titanate nanotubes due to its ion-exchange capability. With the guidance of protection mechanism of core-shell catalysts, the key factors that determined the resistance of the resulted catalysts will be ascertained. The core-shell catalysts developed here show outstanding SCR activity, s

英文关键词： Selective Catalytic Redution；Titanate nanotubes；Solid superacid；Transition metal oxides；Alkaline resistance