Dynamic modelling of a heterogeneously catalysed system with stiff Hopf bifurcations

We report the results of a detailed dynamic modelling of CO oxidation on a platinum catalytic wire, carried out via an iterative parameter estimation scheme which employs both experimental bifurcation-to-oscillation data as well as the actual oscillatory data. By exploiting the stiffness of the system's model equations, some algebraic equations that describe the oscillatory boundaries in the feed temperature/partial pressure parameter space are extracted. The resulting model is shown to fit quantitatively these boundaries and the dynamic oscillographs of the wire temperature and simulate, with satisfactory accuracy, the unfitted dynamic data. Following an extension of the independent parameters space of the model beyond the reported experimental one, interesting bifurcation sequences (including multiple steady states) obtained via a computational study are predicted. The utility of both the resulting model in catalytic reactor design and the novel iteration scheme in general parameter estimation work on catalytic models is discussed.