Acta Phys. -Chim. Sin. ›› 2012, Vol. 28 ›› Issue (06): 1455-1460.doi: 10.3866/PKU.WHXB201203303

• CATALYSIS AND SURFACE SCIENCE • Previous Articles     Next Articles

Novel Method of Controlling Formation of Hot-Spot over Gold Catalysts for CO Oxidation

WANG Fang, WANG Cai-Hong, LI Da-Zhi   

  1. Department of Chemistry & Chemical Engineering, Binzhou University, Binzhou 256603, Shandong Province, P. R. China
  • Received:2011-12-13 Revised:2012-03-29 Published:2012-05-17
  • Contact: WANG Fang E-mail:wangfangosso@yahoo.cn
  • Supported by:

    The project was supported by the Research Fund of Binzhou University, China (2010Y06).

Abstract: Au catalysts supported on Al2O3 and MOx-Al2O3 (M=Fe and Zn) were prepared by the deposition-precipitation method. Their catalytic activities for CO oxidation in the absence and presence of an H2-rich steam at room temperature were investigated in detail. Catalyst bed temperatures were determined directly by a thermocouple. The catalyst surface temperature depended on the volume ratio of O2/CO, and the concentrations of CO and H2. The temperature on the Au/Al2O3 surface can reach 170°C during CO oxidation, and is decreased to 55°C by addition of FeOx. These results indicate that formation of hot-spots on γ-alumina-supported gold catalysts could be controlled by adding an appropriate dopant. The structure of the catalysts was characterized by techniques such as X-ray powder diffraction, X-ray photoelectron spectroscopy and transmission electron microscopy. Addition of a dopant could transfer the active center from Au to AuIII, which resulted in different reaction mechanisms of preferential oxidation of CO in the presence of H2.

Key words: CO oxidation, Dopant, Gold catalyst, Hot-spot

MSC2000: 

  • O643