Mechanism and kinetics parameters of the reduction reaction of NO by CO on Pd/Al2O3 catalyst

Abstract

By means of a mechanism similar to that used by Peden and Permana for the reduction reaction of NO by CO on Rh and the analytical solution of its kinetics equations, a set of kinetics parameters that interpret some experimental results determined at moderate pressures for that reaction on palladium supported on alumina were established. When using those parameters, the kinetics model, studied through the analytic solution of the kinetics equations and Monte Carlo simulations, presents various aspects of interest such as the maximum found in experiments in the literature for production versus CO concentration or temperature and a change in the sign of reaction order with respect to CO and NO between the high- and low-temperature zones, and it shows the characteristic configurations of the adsorbed phase in the square and hexagonal cases. Monte Carlo simulations at high temperatures on a square lattice show a behavior similar to that of the classical model of Brosilow-Ziff, with a phase poisoned with pairs of superficial nitrogens in a diagonal direction.