BIFURCATION AND STABILITY ANALYSIS OF MICROMIXING EFFECTS IN THE CHLORITE-IODIDE REACTION

Experimental investigations of the chlorite-iodide reaction in a flow reactor have shown that its dynamical behavior can be very sensitive t o mixing effects. This finding is of fundamental importance for the ki netic study of chemical oscillators since it implies that (finite-dime nsional) perfectly mixed CSTR models may be insufficient for understan ding their dynamical behavior. The simplest model which includes micro mixing effects has the form of a nonlinear, partial, integro-different ial equation (unsteady-state IEM model). Both parametric continuation and linear stability analysis results are reported for the steady-stat e IEM model using the Citri-Epstein mechanism with the kinetic constan ts employed by Fox and Villermaux (1990, Chem. Engng Sci. 45, 2857-287 6). Numerical results, presented in the form of one- and two-parameter bifurcation diagrams using the mean residence time and the micromixin g time as parameters, are in qualitative agreement with experimental r esults. The existence of periodic solutions after potential Hopf bifur cation points has been verified by transforming the unsteady-state IEM model into an infinite system of ordinary differential equations usin g a Laguerre polynomial expansion, and solving for a truncated set of expansion coefficients. Bifurcation analysis of the steady-state model is shown to be a useful tool for understanding the bifurcation behavi or of the (infinite-dimensional) unsteady-state IEM model.