摘要本文研究了过渡金属钴（Co）掺杂对磁赤铁矿NH3-SCR反应性能的影响。采用共沉淀法合成了γ-Fe2O3、Fe2.8Co0.2O4和Fe2.5Co0.5O4催化剂，在固定床石英管反应器上考察了催化剂NH3-SCR反应性能，并借助XRD、BET、TPD和H2-TPR等表征手段对其理化性质进行了分析。研究结果表明，适量掺杂Co可使磁赤铁矿活性窗口温度向高温方向漂移，并且可抑制NH3在高温段向NO氧化。降低空速可提升催化剂低温段NH3-SCR反应活性。复杂环境条件下，硫化作用和H2O对催化剂NH3-SCR反应性能影响具有一致性：低温段使NOx转化率显著降低，高温段抑制NH3氧化为NO使NOx转化率升高。20766
关键词  磁赤铁矿 Co掺杂 氨气选择性催化还原
毕业论文设计说明书（论文）外文摘要
Title  Effect of Cobalt (Co) Doping on the Selective Catalytic Reduction  of NOx with NH3 over Maghmite                       
Abstract
In this work, the effect of Co doping on the selective catalytic reduction (SCR) reaction over maghemite (γ-Fe2O3) was studied. A series of (Fe3-xCox)1-δO4, γ-Fe2O3, Fe2.8Co0.2O4 and Fe2.5Co0.5O4, were synthesized using a co-precipitation method. The SCR performance of three catalysts were investigated on a fixed-bed quartz tube reactor, followed by the physicochemical characterization of XRD, BET, TPD and H2-TPR. Furthermore, in “clean” conditions, the operation temperature window of maghemite doped with Co shifted to higher temperature and the catalytic oxidation NH3 to NO at high temperature was restrained. The SCR activity of catalyst was promoted with the decrease of gas hourly space velocity (GHSV) especially at low temperatures. The presence of H2O and sulfation showed a dual effect on the SCR reaction over catalyst. NOx conversion decreased at low temperatures, while it increased at high temperatures as the result of the catalytic oxidation NH3 to NO restrained.
Keywords  maghemite   cobalt(Co) doping   NH3-SCR 
目   次
1  绪论    1
1.1  氮氧化物的性质及来源    1
1.2  氮氧化物排放控制技术    1
1.3  氨气选择性催化还原（NH3-SCR）技术    2
1.4  铁基尖晶石氧化物催化剂研究进展    3
1.4.1  铁基尖晶石氧化物晶体结构    3
1.4.2  铁基尖晶石氧化物类质同象置换    3
1.4.3  磁赤铁矿（γ-Fe2O3）催化剂特性    4
1.4.3  过渡金属钴同象置换对铁基尖晶石氧化物的影响    6
1.5  课题的目的、意义及主要研究内容    6
1.5.1  课题的目的及意义    6
1.5.2  主要研究内容    7
2  实验部分    8
2.1  实验材料与实验系统    8
2.1.1  实验试剂与仪器    8
2.1.2  实验系统    8
2.2  催化剂制备    9
2.3  催化剂表征测试    10
2.3.1  X-射线衍射（XRD）分析    10
2.3.2  比表面积（BET）测试    11
2.3.3  程序升温还原（H2-TPR）    11
2.3.4  程序升温脱附（NH3/NO-TPD）测试    11
2.3  催化剂活性评价    11
3  结果与讨论    13
3.1  Co掺杂量对磁赤铁矿NH3-SCR反应性能的影响    13
3.1.1  催化剂活性测试    13
3.1.2  催化剂表征    14 Co掺杂对磁赤铁矿NH3-SCR反应性能的影响:http://www.751com.cn/huaxue/lunwen_12664.html