Kinetic Study of Dry Reforming of Methane Over Ni-Ce/Al2O3 Catalyst with Deactivation

摘要

A kinetic study for dry reforming of methane over Ni-Ce/Al2O3 catalyst was performed, taking into account both the main reactions and the catalyst deactivation. The catalyst was prepared by a sequential wet impregnation process, with loadings of 5 wt.% Ni and 10 wt.% Ce. Experimental tests were carried out in a fixed bed reactor between 475 and 550 degrees C and several spatial times, using nitrogen as diluent. Several kinetic equations were compared. The best fit of experimental data was achieved using a Langmuir-Hinshelwood mechanism which takes into account the presence of two active sites. Pre-exponential factor and activation energy were calculated. the kinetics of deactivation was also determined. The relationship between catalyst activity and coke concentration was also studied. Several deactivation equations were considered in order to choose the best fit with experimental data.