物理化学学报 >> 2015, Vol. 31 >> Issue (4): 743-749.doi: 10.3866/PKU.WHXB201503025

催化和表面科学 上一篇    下一篇

三维有序大孔MgFe0.1Al1.9O4催化剂制备及其催化乙苯与CO2氧化脱氢的性能

李浙齐1, 王特华2, 李秀媛3, 张雅琴2, 纪敏2   

  1. 1 大连交通大学环境与化学工程学院, 辽宁大连116028;
    2 大连理工大学化学学院, 辽宁大连116024;
    3 东北制药集团股份有限公司原料药生产事业部, 沈阳110000
  • 收稿日期:2014-12-11 修回日期:2015-02-11 发布日期:2015-04-03
  • 通讯作者: 纪敏 E-mail:jimin@dlut.edu.cn
  • 基金资助:

    国家自然科学基金(21356001)及大连理工大学基本科研业务费重大项目培育科研专题(DUT12ZD219)资助项目

Preparation and Catalytic Performances of a Three-Dimensionally Ordered Macroporous MgFe0.1Al1.9O4 Catalyst for Ethylbenzene Oxydehydrogenation with CO2

LI Zhe-Qi1, WANG Te-Hua2, LI Xiu-Yuan3, ZHANG Ya-Qin2, JI Min2   

  1. 1 College of Environmental and Chemical Engineering, Dalian Jiaotong University, Dalian 116028, Liaoning Province, P. R. China;
    2 College of Chemistry, Dalian University of Technology, Dalian 116024, Liaoning Province, P. R. China;
    3 API Production Division, Northeast Pharmaceutical Group Co., LTD., Shenyang 110000, P. R. China
  • Received:2014-12-11 Revised:2015-02-11 Published:2015-04-03
  • Contact: JI Min E-mail:jimin@dlut.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21356001) and Fundamental Research Funds for the Central Universities of Dalian University of Technology, China (DUT12ZD219).

摘要:

采用无皂乳液聚合法合成了聚甲基丙烯酸甲酯(PMMA)微球, 并以此为模板制备了具有三维有序大孔(3DOM)结构的MgFe0.1Al1.9O4尖晶石催化剂, 考察了其催化乙苯与CO2氧化脱氢生成苯乙烯反应的性能. 采用X射线衍射、扫描电镜、程序升温还原以及57Fe 穆斯堡尔谱等方法对催化剂的物理化学性质进行表征. 结果表明, 3DOM MgFe0.1Al1.9O4 催化剂具有三维有序大孔结构, 其大孔孔径为230 nm, 孔壁平均厚度为60 nm, 其中大部分Fe物种以同晶取代的方式进入到尖晶石骨架中. 该催化剂在乙苯与CO2氧化脱氢反应中表现出良好的催化活性和稳定性. 通过与具有相同化学组成的nano MgFe0.1Al1.9O4 催化剂对比研究发现, 3DOMMgFe0.1Al1.9O4畅通的孔道结构十分有利于反应积碳前驱物的外扩散, 对提高催化剂的稳定性具有重要作用.

关键词: 三维有序大孔材料, 镁-铁-铝尖晶石, 二氧化碳, 乙苯脱氢, 稳定性

Abstract:

Polymethyl methacrylate (PMMA) microspheres were synthesized using an emulsifier-free emulsion polymerization method. A three-dimensionally ordered macroporous (3DOM) MgFe0.1Al1.9O4 spinel-type oxide catalyst was prepared using the synthesized colloidal crystal templates and evaluated for oxidative dehydrogenation of ethylbenzene with CO2. Several techniques, such as powder X-ray diffraction, scanning electron microscopy, temperature-programed reduction, and 57Fe-Mössbauer spectra, were used to characterize the physicochemical properties of the catalyst. The results indicate that 3DOM MgFe0.1Al1.9O4 has a hexagonal ordered arrangement, with a pore diameter of 230 nm and a shell thickness of 60 nm, and that most of its Fe species are incorporated into the spinel lattice. Compared with a nano MgFe0.1Al1.9O4, the 3DOM MgFe0.1Al1.9O4 catalyst exhibited a much higher catalytic stability and less carbon deposition. A possible explanation for the enhanced catalytic stability of 3DOM MgFe0.1Al1.9O4 catalyst is discussed. The three-dimensionally ordered macroporous structure has a large effect on the diffusion of coke precursors and the stability of the catalyst.

Key words: Three-dimensionally ordered macroporous material, Mg-Fe-Al spinel, Carbon dioxide, Dehydrogenation of ethylbenzene, Stability

MSC2000: 

  • O643