催化学报

催化学报 ›› 2009, Vol. 30 ›› Issue (12): 1233-1237.

• 研究论文 • 上一篇    下一篇

钙铝石涂层对整体型钙钛矿氧化物催化剂活性和热稳定性的影响

陈银飞, 王占龙, 张泽凯   

  1. 浙江工业大学化学工程与材料学院绿色化学合成技术国家重点实验室培育基地, 浙江杭州 310014
  • 收稿日期:2009-12-25 出版日期:2009-12-25 发布日期:2013-09-29

Effect of Mayenite Washcoat on Activity and Thermal Stability of Honeycomb Monolithic La0.8Sr0.2MnO3 Catalyst

CHEN Yinfei, WANG Zhanlong, ZHANG Zekai*   

  1. State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology, College of Chemical Engineering and Materials Science, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, China
  • Received:2009-12-25 Online:2009-12-25 Published:2013-09-29

PDF

813

被引次数

8

摘要： 采用固相反应法合成了钙铝石材料 12SrO•7Al2O3, 并以此作为涂层制备了堇青石蜂窝陶瓷型 La0.8Sr0.2MnO3 整体催化剂, 在不同温度 (850~1 050 oC) 下对该催化剂进行了热处理, 并采用 N2 吸附-脱附、X 射线衍射和扫描电镜等手段对其进行了表征, 考察了其催化甲基丙烯酸甲酯燃烧反应的活性. 结果表明, 12SrO•7Al2O3 作为涂层明显改善了整体催化剂的热稳定性, 在 850 oC 下焙烧 6 h 后, 含有 12SrO•7Al2O3 涂层的整体催化剂在 260 oC 即可将甲基丙烯酸甲酯完全转化. 12SrO•7Al2O3 涂层可避免 La0.8Sr0.2MnO3 活性组分与堇青石的接触, 减轻了活性组分在催化剂表面的烧结, 有利于保持 La0.8Sr0.2MnO3 活性组分的晶体结构和分散度, 提高整体催化剂的活性和热稳定性.

关键词: 钙钛矿, 钙铝石, 堇青石, 甲基丙烯酸甲酯, 催化燃烧, 热稳定性

Abstract: 12SrO·7Al2O3 was synthesized by solid reaction and was used as the washcoat to a La0.8Sr0.2MnO3-cordierite monolith catalyst. The monolith catalyst was treated at different temperatures (850–1050 oC) and was characterized by N2 adsorption-desorption, X-ray diffraction, and scanning electron microscopy. The catalytic activity of the monolith catalyst was evaluated using methyl methacrylate combustion. The results showed that the 12SrO·7Al2O3 washcoat improved the thermal stability of the monolith catalyst obviously. After calcination at 850 oC for 6 h, the monolith catalyst with the 12SrO·7Al2O3 washcoat could fully convert methyl methacrylate at about 260 oC. The 12SrO·7Al2O3 prevented the interaction between La0.8Sr0.2MnO3 and cordierite and alleviated the sintering of La0.8Sr0.2MnO3, and thus kept the structure and the dispersion of La0.8Sr0.2MnO3 and enhanced the activity and thermal stability of the monolith catalyst.

Key words: perovskite, mayenite, cordierite, methyl methacrylate, catalytic combustion, thermal stability