Acta Phys. -Chim. Sin. ›› 2017, Vol. 33 ›› Issue (8): 1681-1688.doi: 10.3866/PKU.WHXB201704192

• ARTICLE • Previous Articles     Next Articles

Catalytic Oxidation of o-Xylene over Pd/γ-Al2O3 Catalysts

Ling-Xiao HU1,2,Lian WANG1,2,Fei WANG1,2,Chang-Bin ZHANG1,2,*(),Hong HE1,2,3,*()   

  1. 1 State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, P. R. China
    2 University of Chinese Academy of Sciences, Beijing 100049, P. R. China
    3 Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, Fujian Province, P. R. China
  • Received:2016-12-28 Published:2017-06-14
  • Contact: Chang-Bin ZHANG,Hong HE E-mail:cbzhang@rcees.ac.cn;honghe@rcees.ac.cn
  • Supported by:
    The project was supported by the National Natural Science Foundation for Excellent Young Scholars, China(21422706);National Natural Science Foundation of China(51678560)

Abstract:

1% (w)Pd/γ-Al2O3 catalysts were prepared by the impregnation method using nano γ-Al2O3 (10 nm) and γ-Al2O3 (200-300 nm) as support materials. The catalysts were tested for catalytic oxidation of o-xylene and the difference of catalyst activity before and after hydrogen reduction was investigated. The results indicate that 1% (w)Pd/γ-Al2O3 (nano) has the highest catalytic activity for o-xylene oxidation after H2 reduction, and the T90 (The temperature of conversion rate of o-xylene reaches 90%) was 150℃. The structure-activity relationships of the catalysts were studied by X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), while the specific surface area was determined using the Brunauer-Emmett-Teller (BET) isotherm. The results show that the reduced Pd is the active species for catalytic oxidation of o-xylene. Pd particle size has a significant influence on the catalyst activity and a small Pd particle size is favorable. There is a strong interaction between the supporter (nano γ-Al2O3) and the Pd species, which facilitates the particle size control and Pd dispersion, thereby increasing the catalyst activity of the 1% (w)Pd/γ-Al2O3(nano) catalyst.

Key words: γ-Al2O3, Noble metal catalyst, Catalytic oxidation, o-Xylene

MSC2000: 

  • O643.36