摘要NOx 会造成酸雨、灰霾、光化学烟雾等环境问题，并且对人体有生物毒性。NH3 选择 性催化还原法（NH3-SCR）因其技术相对成熟高效，已成为控制 NOx 排放的主流技术。 该技术的商用催化剂为 V2O5-WO3/TiO2，但其存在温度窗口窄、V2O5 具有生物毒性等缺 点。因此寻找新型、高效、环境友好型的 SCR 催化剂具有重要的实际意义。73774

Ce-Ti 催化剂具有无毒、廉价、高温活性好的优点，但其低温活性较差，本文将具有 优异低温活性的 Mn-Ce 催化剂与 Ce-Ti 催化剂进行组合，得到一种具有较宽活性窗口、 较高 NOx 转化率的复合床催化剂。将 Ce0。1TiOx 催化剂置于上游，Mn3CeOx 催化剂置于下 游所组成的复合床催化剂，两种催化剂都可以在各自适宜的活性温度窗口内发挥优势。 Ce 物种和 Mn 物种分别为 Ce0。1TiOx 催化剂和 Mn3CeOx 催化剂提供酸性位点，Ce0。1TiOx 催 化剂表面有较多的酸性位点，所以 Ce0。1TiOx 催化剂对 NH3 的吸附能力较强。Mn3CeOx 催 化剂表面所吸附的 NH3 物种活性更高，这是 Mn3CeOx 催化剂表面更容易发生 NH3 氧化的 原因。

毕业论文关键字 Ce-Ti 催化剂 Mn-Ce 催化剂 SCR 反应 复合床 低温优化

毕 业 设 计 说 明 书 外 文 摘 要

Title Medium-Low Temperature  Composite  Bed  Catalyst for Selective Catalytic Reduction of NOx with NH3

Abstract NOx can cause environmental problems such as the formation of acid rain, smog and photochemical smog, and it has biological toxicity to human body。 Due to being a relatively mature with high NOx removal efficiency, selective catalytic reduction (NH3-SCR) is a mainstream technology for NOx abatement。 And the most widely used catalyst system is V2O5-WO3/TiO2, which still shows some actual problems, such as the relatively narrow temperature window and the toxicity of vanadium pentoxide to the environment。 There are continuing efforts for us to develop novel, highly efficient and environmental-friendly NH3-SCR catalysts。

Ce-Ti catalyst with high temperature has advantages of non-toxic, low-cost, but it have a poor activity at relatively low-temperature。 This article will combine a Mn-Ce catalyst which has excellent low-temperature catalyst activity with a Ce-Ti catalyst to obtain a composite catalyst with wider operating temperature window and high NOx conversion rate。 Ce0。1TiOx catalyst was placed upstream of the Mn3CeOx catalyst, both Ce0。1TiOx catalysts and Mn3CeOx catalyst displayed their strong points at their appropriate temperature for the SCR reaction。 Ce and Mn species provide Ce0。1TiOx and Mn3CeOx catalyst acid sites。 However, Ce0。1TiOx catalyst surface have more acidic sites, this is the reason that Ce0。1TiOx catalyst has the  strong  adsorption capacity of NH3。 NH3 species adsorbed on the Mn3CeOx catalyst surface have higher activity, which make NH3 oxidation is more likely to occur on the surface of Mn3CeOx catalyst。

Keywords: Ce-Ti catalyst Mn-Ce catalyst  SCR  reaction  double  layer  catalyst  low temperature promotion

本科毕业设计说明书 第 I 页

目 次

1  引言 1

1。1 氮氧化物污染概论 1

1。2 选择性催化还原技术（NH3-SCR） 1

1。3 Ce 基氧化物催化剂 2

1。4 选题目的、意义及主要研究内容 3

2  实验系统和分析方法 4

2。1 实验材料与设备 4