Au/CuO_x-TiO₂ Catalysts for CO Oxidation at Low Temperature

Feng-Chyi Duh, Der-Shing Lee, Yu-Wen Chen

Department of Chemical and Materials Engineering, National Central University, Chung-Li, Chinese Taipei.
Department of Mechatronic Engineering, Ta Hwa University of Science and Technology, Hsin-Chu, Chinese Taipei.

DOI: 10.4236/mrc.2013.21001                

Abstract

A series of Au/CuO_x-TiO₂ with various Cu/Ti ratios were prepared. CuO_x/TiO₂ was prepared by incipient-wetness im- pregnation with aqueous solution of copper nitrate. Au catalysts were prepared by deposition-precipitation method at pH 7 and 338 K. The catalysts were characterized by inductively-coupled plasma-mass spectrometry, temperature pro- gramming reduction, X-ray diffraction, transmission electron microscopy, high-resolution transmission electron mi- croscopy and X-ray photoelectron spectroscopy. The reaction was carried out in a fixed bed reactor with a feed con- taining 1% CO in air at WHSV of 120,000 mL/h·g. High gold dispersion and narrow size distribution was obtained. The addition of CuO_x in Au/TiO₂ enhanced the activity on CO oxidation significantly. CuO_x was in amorphous state which could stabilize the Au nanoparticles. Cu was in Cu¹⁺ state. Cu donated partial electrons to Au. The interactions among Au, Cu¹⁺ and TiO₂ account for the high catalytic activity for CO oxidation. The significant promotional effect of CuO_x on CO oxidation at low temperature was demonstrated.

Keywords

CO Oxidation; Gold Catalysts; Copper; Nanometal

Conflicts of Interest

The authors declare no conflicts of interest.

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