非表示:
キーワード:
CuO; Fe(OH)x; CuO–Fe2O3; CO oxidation; PROX; Hydrogen purification
要旨:
Ferric hydroxide supported copper oxide (CuO/Fe(OH)x) catalysts were prepared with a simple coprecipitation method and used for selective oxidation of CO in H2-rich gas. The effect of calcination temperatures and Cu loadings on the activity as well as the durability of the catalyst was investigated.
When the calcination temperature was 200 ◦C and the Cu loading was ranging from 7.2 to 17.3 wt%, the
catalyst gave the best performance with total conversion of CO achievable in a wide temperature window from 110 ◦C to 150◦C. To reveal the reason for the high activity of the catalysts, a variety of characterization techniques were employed. The results of XRD and TG–DTA indicated that the catalysts were amorphous even after being calcined at 400 ◦C, which gave rise to large surface areas. HRTEM and XPS
examinations indicated that the surface copper species were Cu2O with particle size of smaller than 5 nm. In situ DRIFT and FT-IR results showed that the reduction of Cu2+ in the composite occurred even below
room temperature when exposed to CO. The significant reducibility might contribute to the high activity of the catalysts.
