(64a) Performance of a Nonlinear Catalytic Tubular Reactor

Chemical systems in which the kinetics of the reaction is coupled to mass diffusion and convective transport are very common in modern chemical process industries such as bioprocesses, catalysis, and biotechnology. These systems are strongly non-linear due to the nature of the reaction kinetics and internal feedback between the other processes (i.e., convection and diffusion). This non-linearity yields a wide variety of non-trivial behaviours such as multiple steady-states, oscillations, and chaos. Moreover, most chemical processes involve some sort of energy exchange, which in return further adds to the nonlinear nature of the processes and to the palette of complex process behaviour.

Many studies have been conducted with systems consisting of reactions in the presence of diffusion and convection, but most of them have looked at systems involving first order reactions with several assumptions to the system. The corresponding dynamics of the systems were studied while performing several simplifications such as a plug flow adiabatic system, a plug flow adiabatic system with a cooling jacket, a laminar flow adiabatic system with no radial mass transport or axial diffusion, a laminar flow adiabatic system with radial and axial diffusion, and a laminar flow non-adiabatic system.

Mass and energy balance equations can be written for these types of systems in the form of partial differential equations (PDE's). These can then be written in terms of non-dimensional parameters in order to form coupled dimensionless equations which can be solved using a variety of numerical techniques. This study aims at investigating the dynamic behaviour of a two-dimensional catalytic tubular reactor, described via a reaction-diffusion-convection model, using numerical modeling. Different process parameters related to heat exchange in the catalyst bed are assessed and their impact on the behaviour of the system in question is analyzed.

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