摘要本文研究了过渡金属Mn和Cr负载于TiO2上形成的5% Mn/TiO2与5% Cr/TiO2催化剂进行NH3-SCR反应的动力学机理。5% Mn/TiO2和5% Cr/TiO2催化剂在NH3-SCR反应进行过程中会伴随NSCR反应和C-O反应的发生，两种副反应与SCR反应属于竞争关系，且高温时竞争更加显著。N2和N2O均能通过Langmuir-Hinshelwood机理及Eley-Rideal机理生成，但是通过Eley-Rideal机理进行的NO还原反应中N2和N2O的生成速率只与气态NO浓度有关，而通过Langmuir-Hinshelwood机理进行的NO还原反应中气态NO和气态NH3的浓度变化对N2和N2O的生成速率均不产生影响。通过建立动力学模型，探究SCR反应、NSCR反应及C-O反应速率的变化规律，发现随着气态NO浓度的升高，SCR反应速率逐渐增大；NSCR反应速率先增大后趋于平稳；C-O反应速率逐渐减缓最终趋于平稳。5% Mn/TiO2催化剂主要通过Eley-Rideal机理进行SCR反应，而5% Cr/TiO2催化剂主要通过Langmuir-Hinshelwood机理进行SCR反应。78506

毕业论文关键词  NH3-SCR反应  Eley-Rideal机理  Langmuir-Hinshelwood机理  动力学模型

毕业设计说明书外文摘要

Title      Kinetic mechanism study of the selective catalytic reduction of NO with NH3 over TiO2 supported transition metal catalysts                                       

Abstract In this work, the kinetic mechanism of the selective catalytic reduction of NO with NH3 over 5% Mn/TiO2 and 5% Cr/TiO2 was studied。 In the process of NH3-SCR reaction, the nonselective catalytic reduction (NSCR) reaction and the catalytic oxidation of NH3 to NO (C-O reaction) simultaneously happened both over 5% Mn/TiO2 and 5% Cr/TiO2。 The two kinds of side reactions and the SCR reaction are competitive relations especially at high temperatures。 The Langmuir-Hinshelwood mechanism and the Eley-Rideal mechanism both contributed to N2 and N2O formation。 Meanwhile the rates of N2 and N2O formation were related with gaseous NO concentration through the Eley-Rideal mechanism and both independent of gaseous NO and NH3 concentration through the Langmuir-Hinshelwood mechanism。 With the increase of the gaseous NO concentration, the rate of SCR reaction increased gradually, the rate of NSCR reaction increased at first and then tended to be stable and the rate of C-O reaction gradually slow down and then tended to be stable through establish the dynamic model to explore the variation law of the SCR reaction, NSCR reaction and C-O reaction rate。 The SCR reaction over 5% Mn/TiO2 mainly through the Eley-Rideal mechanism and the SCR reaction over 5% Cr/TiO2 mainly through the Langmuir-Hinshelwood mechanism。

Keywords  NH3-SCR reaction  Eley-Rideal mechanism  Langmuir-Hinshelwood mechanism  kinetic model 

目   次

1　绪论 1

1。1　氮氧化物的来源 1

1。2　氮氧化物的危害 1

1。3　烟气脱硝发展前景 1

1。4　氨选择性催化还原技术 2

1。5　本课题的研究内容及目的 3

2　实验部分 4

2。1　实验材料与实验系统 4

2。2　催化剂制备 6

2。3　催化剂活性评价 6

2。4　X-射线衍射（XRD） 7

2。5　原位红外实验 7

2。6　瞬态反应 7