Acta Phys. -Chim. Sin. ›› 2014, Vol. 30 ›› Issue (5): 950-956.doi: 10.3866/PKU.WHXB201403111

• CATALYSIS AND SURFACE SCIENCE • Previous Articles     Next Articles

Low-Temperature Total Oxidation of Toluene over Assembled Pt/TiO2 Catalyst

AO Ping, XU Xiang-Sheng, XU Xiao-Xiao, LI Jia-Heng, YAN Xin-Huan   

  1. State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Zhejiang University of Technology, Hangzhou 310014, P. R. China
  • Received:2013-12-06 Revised:2014-03-11 Published:2014-04-25
  • Contact: YAN Xin-Huan E-mail:xinhuanyan139@hotmail.com
  • Supported by:

    The project was supported by the National High Technology Research and Development Program of China (863) (2013AA065005).

Abstract:

A highly active assembled Pt/TiO2 catalyst (Pt/TiO2-AS) was synthesized using a simple directadsorption method, in which uniformly dispersed Pt nanoparticles were directly loaded on a TiO2 support. Compared with Pt/TiO2 produced by wet impregnation (Pt/TiO2-WI), the Pt/TiO2-AS catalyst exhibited higher activity in the total oxidation of toluene, with a toluene conversion to CO2 and H2O of 100% at 150 ℃. The high activity remained even at high toluene concentrations and gas hourly space velocities. The properties of the synthesized catalysts were characterized using X- ray diffraction (XRD), N2 adsorption- desorption (Brunauer-Emmett-Teller (BET) method), transmission electron microscopy (TEM), X- ray photoelectron spectroscopy (XPS), temperature-programmed reduction of H2 (H2-TPR), and Fourier-transform infrared (FTIR) spectroscopy. The results showed that the Pt/TiO2-AS crystallites were smaller than those of Pt/TiO2-WI, with fine dispersion, greater Pt0 exposure on the support surface, and more active Ti―O bands, giving more oxygen vacancies and reactive oxygen species. The valence states of the active centers changed significantly (Pt0→Ptδ+) during stability tests; this is the main reason for the deactivation of the Pt/TiO2-AS catalyst.

Key words: Platinum, Titanium dioxide, Assembled catalyst, Toluene, Total oxidation

MSC2000: 

  • O643