A Model for the catalytic reduction of CO on a surface with variable reaction rate, CO desorption and impurities

Kinetic Monte Carlo simulations are applied to study a modified Ziff-Gulari-Barshad (ZGB) model for the catalytic oxidation of carbon monoxide on a surface. The original model has been made more realistic by incorporating temperature effects such as desorption of the CO , a variable reaction rate probability, and the existence of contaminants in the feeding gas. Several of these effects have already been studied separately, in this work we consider how they alter the system when considered simultaneously. We found that the combination of these processes strongly modifies the phase diagram of the original model, in many cases eliminating the abrupt phase transition towards a nonreactive state. And although the lessening of the reaction probability and the presence of impurities clearly reduce the productivity of the system, these effects can be counteracted by the CO desorption and obviously by the impurity desorption.