Selective Removal of CO in Hydrocarbons-Rich Industrial Off-gases over CuO–CexZr1−xO2 Catalysts

Abstract

The selective remove CO in industrial rich-hydrocarbon off-gases was performed over CuO–CexZr1−xO2 (x = 0, 0.1, 0.5, 0.75, 0.9 and 1.0) mixed oxides. The effect of ceria content on the structure and catalytic properties of CuO–CexZr1−xO2 compositions has been investigated, and the removal activity of CO is greatly dependent the structure of the support. Based on the characterizations from XRD, H2-TPR, Raman spectra, XPS and CO-TPD, it can be found that the formation of ceria–zirconia solid solution induced by the introduction of ceria into zirconia leads to an increase in the amount of oxygen vacancies and the mobility of the lattice oxygen, and as a result, enhances the removal activity of catalysts towards CO. The lowest reaction temperature (~ 123 ℃) for 100% conversion of CO remove was obtained over CuO–Ce0.9Zr0.1O2 sample, which also exhibited the highest concentration of surface oxygen vacancy, the better reducibility and the highest low-temperature adsorption capacity of CO. This study presents a strategy to design a high-efficiency CuO-based catalyst by controlling the concentration of the surface oxygen vacancies.