Selective Removal of CO in Hydrocarbons-Rich Industrial Off-gases over CuO-Ce_xZr_(1-x)O_2 Catalysts

摘要

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, H-2-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 (similar to 123 celcius) 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.