Development of a kinetic model of lean-nox-trap and validation through a reactive CFD approach

Our activity is focused on the study of the kinetic of the Pt-Ba/γ-Al2O3 catalyst used in the Lean-NOx-Traps to store NOx as adsorbed nitrites and nitrates, and to reduce them to nitrogen. Kinetically relevant data have been collected by the Laboratoire Catalyse et Spectrochimie (ENSICAEN, France), using a spectroscopic reactor-cell, and on the basis of the collected data, a kinetic model has been developed, using as experimental responses the dynamic evolution of both the gas phase and the adsorbed species. In this work a reactive CFD-based modeling approach is proposed for the first time, in order to keep into account the actual reactor-cell geometry (modeled as ideal PFR for the estimate of the kinetic parameters), and to obtain further information of the space-time evolution of the reactive system. Consequently, a new simulation tool, named CATalytic Post Processor, is here presented. CAT-PP is able to acquire the flow/velocity field obtained by the commercial code ANSYS Fluent and to solve the transport equations containing the kinetic scheme.