【作者】 杨青山；

【导师】 张志刚；

【作者基本信息】 华东理工大学 ， 工业催化， 2011， 硕士

【摘要】 活性氧化铝粉体的预处理对于增强其在整体式陶瓷载体上的粘结负载和控制料浆的性能有着重要的作用。本文采用气体粉碎机(GSM)预处理高比表面积的活性氧化铝(γ-Al2O3-b),用其制备的料浆有好的流动性和负载率,其最大的特点是在料浆的制备过程中不需要球磨,为下一步制备整体式选择性催化还原(SCR)催化剂提供了有利条件。本文采用Fe、Mn为主要催化活性组分制备整体式SCR催化剂,用NH3作还原剂。催化剂的制备方法是Fe、Mn和经预处理的γ-Al2O3-b一起调制成涂覆的料浆,一次涂覆到整体式陶瓷载体上,采用此种方法制备催化剂简单,易操作,并且催化活性较高,在空速5200h-1、NH3/NOX比1.0、反应温度180-320℃范围内,NOx达到完全转化。通过利用H2-TPR、NH3-TPD和situ DRIFTS研究催化剂表面活性组分的氧化物形态,以及在反应过程中气体在活性中心吸附的状态,从而研究催化反应的过程。Fe的部分取代使得Mn的H2-TPR低温峰向低温方向移动,促进了反应的活性提高,同时Fe也有利于NH3在催化剂表面的吸附并参与反应。NOx的吸附能力比NH3强,当二者达到竞争吸附平衡时反应的活性最高,同时,在Fe1/Mn2-Al2O3的表面反应气体的吸附峰最强,验证了其好的反应活性。更多还原

【Abstract】 Special pretreatment with Gas Smash Machine (GSM) forγ-Al2O3 is very effective way to enhance adherence to the ceramic and control character of the slurry through change of the particle size distribution.γ-Al2O3-b(showed in table 1) has high surface area and appropriate particle size distribution, which makes the slurry to own excellent adherence and fluidness. Fe and Mn are all prospective transfer metal for the selective catalytic reduction (SCR) of NOx with NH3 and more environmental, meanwhile, they can be added into alumina slurry directly during preparation of ceramic catalyst, which can save amount of work time and procedure. Under the preparation of monolithic catalyst, the conversion of NOx is 100% between 180-320℃, under the molar ratios of NOX/NH3=1.0, and GHSV is 5200 h"1.With the H2-TPR, NH3-TPD and situ DRIFTS, we have researched the oxide of active elements on the surface of catalysts, and absorption of reaction gas on catalysts. As Fe Substituted by Mn, the reduction peak in low temperature of MnOx has been transferred to lower region according to H2-TPR. Meanwhile, FeOx can improve absorption of NH3 to enhance SCR activity. From the situ DRIFTS, absorption of NOX is stronger than NH3 on the Fe1/Mn2-Al2O3, when the two reaction gas arrive at balance points on catalyst, its peak strength absorption of reaction gas is the highest on all catalysts, which also means it has the best conversion of NOX.更多还原