A Kinetic Study of NO Reduction by CO over a NiO/Al_2O_3 Catalyst

摘要

The activity and the kinetics of NO reduction by CO over a reduced low loaded (3wt% in Ni) NiO/Al_2O_3 catalyst were studied. Activity tests show that phase changes (Ni-Nii_2O_3-NiO-NiAl_2O_4) of the active substance caused by temperature and interactions with the reactants cause significant changes on the activity and the mechanism of the reaction. Kinetic measurements performed in the temperature region between 460 and 540℃ and for partial pressures of the reactants between 0.0025 and 0.04atm depicted that the reaction follows a nonequilibrium, "double-site" mechanism. The mathematical expression describing the reaction rate was derived and the respective constants were calculated.