A coordinated experimental and theoretical study of the evolution, selection, stability, and impact of spatiotemporal temperature pattern formation on single, three-dimensional, catalytic pellets and in radial-flow reactors will be carried out. An infrared thermal imager will be used to measure the temperature patterns on the top and sides of cylindrical pellets in a custom-built continuous flow stirred tank reactor. The study will determine the possible patterns, their dependence on operating conditions, and the influence of interparticle transport limitations and pellet size. Model reactions include the oxidation of carbon monoxide on palladium catalysts and the oxidation of hydrogen on a nickel catalyst. Experiments in a radial-flow reactor will provide information about the types of temperature patterns that may evolve. This information can be used to develop control strategies. The study will also provide information about the conditions leading to the formation of hot spots, an event which may lead to severe safety problems in commercial reactors. This information is needed for the rational development of operation and control policies that circumvent their hazardous formation. Theoretical and computational studies will be conducted to simulate the experimental systems and to help find optimal regions of operation.
