高等学校化学学报 ›› 2017, Vol. 38 ›› Issue (11): 2006.doi: 10.7503/cjcu20170192

• 物理化学 • 上一篇    下一篇

钾负载量对CuO/K2CO3/MgAl2O4催化剂高温NOx储存还原性能的影响

刘瑶瑶1, 丁彤1(), 赵东越1, 高中楠1, 郭丽红1,2, 田野1, 李新刚1   

  1. 1. 天津化学化工协同创新中心, 天津市应用催化科学与工程重点实验室,天津大学化工学院, 天津 300354
    2. 河南工业大学化学化工学院, 郑州 450001
  • 收稿日期:2017-03-29 出版日期:2017-11-10 发布日期:2017-10-16
  • 作者简介:联系人简介: 丁 彤, 女, 博士, 副教授, 主要从事环境催化方面的研究. E-mail: d_tong@tju.edu.cn
  • 基金资助:
    国家自然科学基金(批准号: U1232118)和天津市自然科学基金(批准号: 15JCZDJC37400, 15JCYBJC23000)资助

Effect of Potassium Loading on the NOx Storage and Reduction Performance of the CuO/K2CO3/MgAl2O4 Catalyst at High Temperature

LIU Yaoyao1, DING Tong1,*(), ZHAO Dongyue1, GAO Zhongnan1, GUO Lihong1,2, TIAN Ye1, LI Xingang1   

  1. 1. Collaborative Innovation Center of Chemical Science and Engineering(Tianjin),Tianjin Key Laboratory of Applied Catalysis Science and Engineering,School of Chemical Engineering & Technology, Tianjin University, Tianjin 300354, China
    2. School of Chemistry and Chemical Engineering, Henan University of Technology, Zhengzhou 450001, China
  • Received:2017-03-29 Online:2017-11-10 Published:2017-10-16
  • Contact: DING Tong E-mail:d_tong@tju.edu.cn
  • Supported by:
    † Supported by the National Natural Science Foundation of China(No.U1232118) and the Natural Science Foundation of Tianjin, China(Nos.15JCZDJC37400, 15JCYBJC23000)

摘要:

制备了适用于高温氮氧化物储存还原(NSR)反应的CuO/K2CO3/MgAl2O4非贵金属催化剂, 考察了钾负载量对催化剂NSR性能的影响, 发现钾主要以高分散K2CO3和体相K2CO3的形式存在. 在稀燃条件下, NOx在体相K2CO3上形成了高温稳定的硝酸盐物种, 而高分散K2CO3上形成的硝酸盐的高温稳定性则较差. 当钾负载量较低时, 催化剂的NOx储存能力有限, K2CO3主要以高分散形式存在, 稀燃阶段形成的硝酸盐的热稳定性较低, 高温NSR活性较低; 而钾负载量过高时, K2CO3则会覆盖CuO活性位, 从而降低催化剂的NSR活性. 在450 ℃的高温条件下, 钾负载量为10% 时, 所制备催化剂的NOx储存还原能力最佳, NOx还原效率达到99.9%, 是一种具有潜在应用前景的高温NSR催化剂.

关键词: 高温, 非贵金属, 钾负载量, 热稳定性, CuO/K2CO3/MgAl2O4催化剂, NOx储存还原

Abstract:

We designed a new NOx storage and reduction(NSR) CuO/K2CO3/MgAl2O4 catalyst operating at high temperature. The effect of potassium loading on the NOx storage and reduction performance of the catalyst was studied. In the catalyst, the K2CO3 exists as highly dispersed K2CO3 and bulk K2CO3. In the lean-burn period, the nitrates formed on the bulk K2CO3 have high thermal stability at high operating temperature, while the thermal stability of the nitrates formed on the highly dispersed K2CO3 is low. When the K loading is low, the K2CO3 mainly exists as highly dispersed K2CO3, the limited NOx storage capacity and the low thermal stability of the nitrates result in the low NSR activity at high temperature. While too much K2CO3 loaded on the catalyst can decrease the redox ability of CuO by covering it, which will decrease the NSR activity of the catalysts. When the K loading is 10%, the best NSR activity is obtained with the highest NOx reduction percentage of 99. 9% at 450 ℃. Therefore, the CuO/K2CO3/MgAl2O4 catalyst is a promising high-temperature NSR catalyst.

Key words: High temperature, Non-noble metal, Potassium loading, Thermal stability, CuO/K2CO3/MgAl2O4 catalyst, NOx storage and reduction

中图分类号: 

TrendMD: