Low-Temperature CO Oxidation on Au/FexOy Catalysts

Abstract

Supported gold catalyst has been reported to have high CO oxidation activity at low-temperature. The aim of this study was to develop a Au/FexOy catalyst that is active under ambient conditions, is low-cost, is resistant to moisture, and has high stability. Iron oxide was chosen because it is cheap and resistant to moisture. A method to prepare a FexOy support that has a higher surface area and abundant hydroxyl groups on the surface was developed. The FexOy was prepared with a very low feeding rate of FeCl3 (10 mL/min), at a constant pH of 10, was dried at 120 °C, and had a very high surface area with abundant hydroxyl groups. The surface area of FexOy was as high as 400 m2/g. It was used as a support for gold in low-temperature CO oxidation. Supported gold catalysts were prepared by deposition−precipitation (DP) using HAuCl4 as the Au precursor under various pH values and calcined at various temperatures. The catalysts were characterized by atomic absorption spectroscopy, X-ray diffraction (XRD), N2 sor...