Release Time:2019-03-09  Hits:

Indexed by: Journal Article

Date of Publication: 2014-12-01

Journal: GOLD BULLETIN

Included Journals: Scopus、EI、SCIE

Volume: 47

Issue: 4

Page Number: 275-282

ISSN: 0017-1557

Key Words: Pretreatment atmosphere; CO oxidation; Gold catalyst; Stability; DRIFTS

Abstract: Hierarchically organized gamma-Al2O3 hollow microspheres were prepared via a hydrothermal method using potassium aluminum sulfate and urea as reactants. The corresponding Au/Al2O3 catalysts were obtained using a deposition-precipitation (DP) method. The effect of the pretreatment under different atmospheres (N-2, air, and H-2) on the activity and stability of the Au/Al2O3 catalysts in CO oxidation was investigated. The results showed that the pretreatment under H-2 atmosphere improved the low-temperature CO oxidation activity. Furthermore, a 50 h long-term test at 30 degrees C showed no significant deactivation for the H-2-pretreated catalyst. Moreover, the catalytic activity was promoted by H2O vapor in all cases, and the H-2-pretreated catalyst exhibited a good tolerance in the co-presence of CO2 and H2O. Finally, oxygen temperature-programmed desorption (O-2-TPD) and in situ diffuse reflectance infrared Fourier transform spectra (DRIFTS) revealed that the reductive atmosphere pretreatment greatly improved the CO adsorption capacity and facilitated the oxygen activation.