Clean Technology 2008
H. Yahiro, K. Saiki, T. Yamamoto, K. Sagata, M. Asamoto, H. Yamaura
Ehime University, JP
hydrogen, copper catalyst, wgs reaction, iron oxide
The catalytic activity of water-gas-shift (WGS) reaction was investigated for alumina-supported copper and copper-iron oxides catalysts calcined at different temperatures. Alumina-supported copper catalysts calcined at 1073 K, followed by the treatment in H2 at 523 K, showed a high activity for WGS reaction. X-Ray diffraction and hydrogen-temperature programmed reduction (TPR) measurements revealed that the catalyst calcined at 1073 K contained both highly dispersed particles of both copper oxide and copper-alumina spinel. The former species was reduced by hydrogen at 523 K to yield the highly dispersed metallic copper which would act as catalytically active sites in WGS reaction. The effect of the addition of iron oxide to alumina-supported copper was also investigated. The activity of alumina-supported copper-iron oxide catalyst with 0.5 of Fe/Cu molar ratio was higher than that of alumina-supported copper catalysts. TPR results suggest that FeOx added was easily reduced by the coexistence of metallic Cu. Therefore, it is concluded that not only metallic Cu but also partially reduced FeOx act as the catalytically active sites for WGS reaction.