物理化学学报 >> 2013, Vol. 29 >> Issue (05): 10481048-1054.doi: 10.3866/PKU.WHXB201303051

催化和表面科学 上一篇    下一篇

(CeO2)x-(La-Al2O3)1-x复合氧化物对柴油车尾气中可溶性有机成分的催化氧化

陈永东, 王磊, 关小旭, 刘永兵, 龚茂初, 陈耀强   

  1. 1 西南石油大学, 油气藏地质及开发工程国家重点实验室, 成都 610500;
    2 西南化工研究设计院有限公司, 成都 610225;
    3 四川大学化学学院, 绿色化学与技术教育部重点实验室, 成都 610064
  • 收稿日期:2012-12-06 修回日期:2013-03-05 发布日期:2013-04-24
  • 通讯作者: 陈永东, 陈耀强 E-mail:chemcyd@tom.com; chenyaoqiang@scu.edu.cn
  • 基金资助:

    国家自然科学基金(21173153); 四川省教育厅一般项目(12ZB163); 绿色催化四川省高校重点实验室开放课题基金(LYY1101); 四川省科技创新苗子工程项目(2012ZZ072)和西南石油大学校级科技基金(2012XJZ037)资助

Catalytic Oxidation of Soluble Organic Fraction in Diesel Exhausts Using Composite Oxides (CeO2)x(La-Al2O3)1-x

CHEN Yong-Dong, WANG Lei, GUAN Xiao-Xu, LIU Yong-Bing, GONG Mao-Chu, CHEN Yao-Qiang   

  1. 1 State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, P. R. China;
    2 Southwest Research & Design Institute of Chemical Industry, Chengdu 610225, P. R. China;
    3 Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, P. R. China
  • Received:2012-12-06 Revised:2013-03-05 Published:2013-04-24
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21173153), Scientific Research Fund of Sichuan Provincial Education Department, China (12ZB163), Opening Project of Key Laboratory of Green Catalysis of Sichuan Institutes of High Education, China (LYY1101), Runner Technology Innovation Project of Sichuan Province, China (2012ZZ072), and Science and Technology Foundation of Southwest Petroleum University, China (2012XJZ037).

摘要:

采用共沉淀法制备了一系列(CeO2)x-(La-Al2O3)1-x复合氧化物(其中x为质量分数, x=0.00, 0.25, 0.50, 0.75, 1.00), 以其为催化剂. 采用热重-差热分析(TG-DTA)法模拟测试该系列催化剂对柴油车尾气中可溶性有机成分(SOF)的催化氧化性能. 结果表明, 当x=0.75时, 催化剂活性最高, 可使SOF在125℃起燃, 355℃完全转化. 并用低温N2吸附-脱附, 储氧量(OSC)测试, X射线衍射(XRD), X射线光电子能谱(XPS)和H2程序升温还原(H2-TPR)等手段对催化剂进行了表征. 研究结果表明, 适量La 和Al 共掺杂增大了氧化铈的比表面积和催化剂中Ce3+所占的比例, 从而提高了催化剂对SOF的低温吸附能力和催化剂的储释放氧能力, 因而提高了催化剂对SOF的氧化活性. 所制备的(CeO2)0.75-(La-Al2O3)0.25复合氧化物适合应用到柴油车尾气净化催化剂中.

关键词: 铈, 铝, 复合氧化物, 可溶性有机成分, 催化氧化

Abstract:

A series of catalytic composite oxides (CeO2)x(La-Al2O3)1-x (with mass fractions x=0.00, 0.25, 0.50, 0.75, 1.00) was prepared using a co-precipitation method. Thermogravimetric-differential thermal analysis (TG-DTA) was used to determine the performances of these composite oxides in the catalytic oxidation of the soluble organic fraction (SOF) of diesel exhaust. The results show that the catalyst with the highest activity, i.e., x=0.75, enabled the SOF to light-off at 125℃ and completely converted the SOF at 355℃. The catalysts were characterized using low-temperature N2 absorption-desorption, oxygen-storage capacity (OSC) measurements, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and H2 temperature-programmed reduction(H2-TPR). The results indicate that co-doping appropriate amounts of La and Al into the catalyst increases the specific surface area of the cerium oxide and the proportion of Ce3+ in the catalyst. This may improve the catalyst's adsorption abilities at low temperature and its OSC, enhancing its activity in SOF oxidation. These (CeO2)0.75(La-Al2O3)0.25 composite oxides are promising catalysts for diesel oxidation.

Key words: Cerium, Aluminum, Composite oxide, Soluble organic fraction, Catalytic oxidation

MSC2000: 

  • O643