Kinetics modeling of the deactivation-regeneration of Cu/SiO2 catalysts with residual activity

CAMILO I. MEYER; MATIAS GARIOS; ALBERTO J. MARCHI; ANTONIO MONZON; TERESITA F. GARETTO

Salamanca, España

Congreso; EuropaCat IX; 2009

In this work deactivation of Cu/SiO2 supported catalyst in the hydrogenation of maleic anhydride in gas phase at atmospheric pressure was studied. This reaction was performed at two temperatures: 170 ºC and 220 ºC and two contact times: 11,9 y 23,8 g.h/mol. The Cu/SiO2 catalyst was prepared by wetness impregnation method and characterized by N2 physisorption at -196 ºC, N2O decomposition at 90 ºC, X ray diffraction and temperature programmed reduction. Under the conditions used in this work the Cu/SiO2 catalyst showed an important conversion drop with time. In order to analyze the causes of this deactivation, experiences at different reaction temperatures and residence times were performed. Catalyst regeneration feasibility under two different atmospheres, oxidizing or reducing, was also analyzed. The experimental results were conveniently fitted using a deactivation model with residual activity by non linear regression. Estimates of kinetic constants for deactivation and regeneration were obtained from this fitting.