J. Phys. IV France 7 (1997) C2-897-C2-898
An EXAFS Study on CuCl/NaY and CuCl/γAl2O3 SystemsY. Xie1, Z. Liu1, X. Cai1, Z. Ren1 and T. Tanaka2
1 Department of Chemistry, Peking University, Beijing 100871, P.R. China
2 Department of Molecular Engineering, Kyoto University, Sakyo-ku, Kyoto 606-01, Japan
XAFS evidence shows that the dispersed Cu+ ions of CuCl/γAl2O3 or CuCl/NaY have changed their coordination structure. Below the maxima of dispersion amounts (thresholds) with increase of contents, O neighbors of Cu decrease and Cl neighbors increase.When the loadings get to the thresholds, the coordination numbers of Cu-O and Cu-Cl of the dispersed phase keep constant values. The results combing the adsorption behavior of systems indicate that although when CuCl disperses on γAl2O3 or NaY, Cu tends to coordinate with O on the surface of the support first, and the coordination mode has been changed, it has no influence to the adsorption ability and the key to improving the adsorption behavior is to increase the surface area and the dispersion amount.
© EDP Sciences 1997