DRIFTS Study of Cu1Zr1Ce9O delta Catalysts for Selective CO Oxidation

作者：Zou Han bo^*; Chen Sheng zhou; Wang Qi ying; Liu Zi li; Lin Wei ming

来源：Spectroscopy and Spectral Analysis, 2010, 30(8): 2103-2106.

DOI：10.3964/j.issn.1000-0593(2010)08-2103-04

• Selective carbon monoxide oxidation
• Cu1Zr1Ce9O delta catalysts
• In-situ DRIFTS
• Pretreatment

The Cu1Zr1Ce9O delta catalysts synthesized with coprecipitation method were used into the selective CO oxidation in hydrogen-rich gas. The adsorbed species and the intermediates on Cu1Zr1Ce9O delta catalysts were examined by in-situ diffuse reflectance FTIR spectroscopy (in-situ DRIFTS) technique. It was found that hydrogen, oxygen and CO in the feed stream were adsorbed competitively at the same adsorption sites on the surface of Cu1Zr1Ce9O delta catalysts. The pretreatment with hydrogen caused the deep reduction of Cu+ species to Cu-0 species and decreased the capacity of CO adsorption on the catalyst surface. The Cu1Zr1Ce9O delta catalyst pretreated with oxygen offered more active oxygen species and inhibited the deep reduction of Cu+ species. The helium pretreatment only purified the surface of Cu1Zr1Ce9O delta catalyst. Two IR bands at 2 938. 7 and 2 843. 8 cm(-1) due to bridged formate and bidentate formate species appeared at 180 degrees C. The active oxygen anion of Cu1Zr1Ce9O delta catalyst could react with CO and produce carbonate species at room temperatures. The carbonate and formate species occupied the adsorption sites and deteriorated the catalytic performance of Cu1Zr1Ce9O delta. Flushing the Cu1Zr1Ce9O delta catalyst with helium at 300 degrees C, the bidentate formate species on the catalyst surface decomposed to monodentate carbonate species and then further decomposed to CO2, which could release the adsorption sites and restore well the catalytic activity.

• 出版日期2010-8
• 单位广州大学