The sensitivity behavior of the fired-bed catalytic reactors is examin
ed using the pseudohomogeneous two-dimensional model with radial dispe
rsion for the first-order irreversible reaction. The sensitivity crite
ria developed are tested. The relations between self-similarity and th
ermal runaway are studied. The pseudoadiabatic type of operation is ta
ken into consideration. The boundaries of the sensitivity region in th
e space Da-Pe are compared with those predicted by the standard one-di
mensional model and the criterion of Hagan et al. The sensitivity beha
vior of the system in the space alpha-Bi is also discussed.