Author/Authors :
G. Leofanti، نويسنده , , A. Marsella، نويسنده , , B. Cremaschi، نويسنده , , M. Garilli، نويسنده , , A. Zecchina، نويسنده , , G. Spoto، نويسنده , , S. Bordiga، نويسنده , , P. Fisicaro، نويسنده , , C. Prestipino، نويسنده , , F. Villain، نويسنده , , C. Lamberti، نويسنده ,
Abstract :
A complete catalytic cycle was performed on CuCl2/Al2O3 catalyst for ethylene oxychlorination at 500 K. X-ray absorption near-edge spectroscopy, extended X-ray absorption fine structure, electron paramagnetic resonance, and IR of adsorbed CO were used to demonstrate that the ethylene oxychlorination reaction, C2H4+2HCl+1/2 O2→C2H4Cl2+H2O, follows a three-step mechanism: (i) reduction of CuCl2 to CuCl (2CuCl2+C2H4→C2H4Cl2+2CuCl), (ii) oxidation of CuCl to give an oxychloride (2CuCl+1/2 O2→Cu2OCl2), and (iii) closure of the catalytic circle by rechlorination with HCl, restoring the original CuCl2 (Cu2OCl2+2HCl→2CuCl2+H2O). The dispersing/sintering effect of the different reagents on the active phase has been also investigated.
