This work analyzes pattern formation mechanisms in the homogeneous model of a fixed catalytic bed for reactions with oscillatory kinetics. Two cases are analyzed: a nonadiabatic reactor with a continuous mass-supply (either by a preceding reaction or via a membrane wall), and a simple adiabatic or cooled reactor. In the former case, the system may reach asymptotic space-independent solutions, and when bistability of such solutions exists fronts may be established. Stationary or oscillatory front solutions, oscillatory states that sweep the whole surface, or excitation fronts may be realized then and the reactor behavior can be predicted from the sequence of phase planes spanned by the reactor. In an adiabatic reactor, fronts are formed only for sufficiently small Pe numbers, but these frontlike solution do not separate different steady states. The patterns that can be realized in this case are quite similar to those in the previous case. The reactor behavior can be predicted by the sequence of phase planes spanned by the reactor, using an approximate finite difference presentation.