Development of a microstructured reactor for heterogeneously catalyzed gas phase reactions: Part II. Reactor characterization and kinetic investigations

A new type of microstructured reactor was characterized and tested in the oxidative dehydrogenation of propane (ODP) with respect to reaction engineering aspects. Residence time behavior was measured using O2/N2 step injection experiments and theoretically analyzed by applying the axial dispersion model, resulting in Bodenstein numbers in the range of 70. Catalytic performance in the ODP was predicted on the basis of a kinetic model from the literature, showing good agreement for low degrees of propane conversion. In order to elucidate discrepancies between experimental and forecasted model data at higher degrees of propane conversion (i.e., >12.5%), possible sources of error were systematically investigated. Specifically, heat and mass transport limitations were excluded as well as possible inaccuracies of the applied kinetic model were examined. It could be shown that microstructured reactors are well suited to be applied for strongly exothermic heterogeneously catalyzed gas phase reactions since they allow isothermal reaction conditions over a wide range of concentrations and temperatures.