Ammonia oxidation over d-band metal catalysts: Modeling complex behavior

MATÍAS RAFTI, A. ALBESA,C. LANCIONI, G. MEDINA Y J.L. VICENTE

Recent Research Developments in Chemical Physics

Transworld Research Network

Lugar: Kerala; Año: 2012;

Abstract. In this communication we will introduce some general aspects of ammonia oxidation reactions performed on stainless steel vacuum chambers operated as flux reactors. Aside from the importance of these systems as model catalytic surfaces, we will discuss a number of interesting   features related to the complex behavior observed; i.e., hysteresis on reaction rates, and spatiotemporal pattern formation. Surface sensitive techniques such as Photoemission Electron  Microscopy (PEEM), X-ray Photoelectron Spectroscopy (XPS) and rate measurement via Quadrupole Mass Spectroscopy (QMS) provide the main experimental input while modeling is carried by using numerical integration of Ordinary Differential Equations (ODE) and Partial Diff. Eq. (PDE) as obtained from suitable derived ad-hoc reaction-diffusion models. New findings based on numerical simulations for Pt(533) are presented, and the possibility of adiabatic elimination of fast variables is demonstrated.