The fixed-bed reactor with periodical flow reversal attains a stable autothermal operating condition, even for a weak exothermal reaction. Periodical flow reversal has also been proposed for the treatment of gases with traces of N2O. At higher temperatures a hybrid reaction can arise, i.e., in addition to the heterogeneous catalytic reaction a homogeneous thermal reaction also takes place. The following paper examines the influence of an axially structured monolith catalyst on the hybrid N2O decomposition process in order to understand the coupling mechanisms in more detail using the reverse flow reactor as a diagnostic tool. Recent studies have demonstrated the potential of the direct calculation of cyclic steady states, in which the regular initial-value problem is transformed into a cyclic steady-state boundary-value problem. In combining this technique with standard bifurcation analysis tools, it is now possible to study the influence of key parameters on the process in a very efficient and elegant way. Both simulations and experimental investigations were required to design an appropriate arrangement for spatial and temporal resolution of the two underlying reaction routes. (c) 2005 Elsevier Ltd. All fights reserved.