Yield Effects in Single and Coupled Nonlinear Thermokinetic Reaction Systems

Abstract

The influence of nonlinear dynamic effects on yield is considered for consecutive-parallel reaction schemes in a single phase CSTR. In the first part, the behavior of a single uncoupled reactor is investigated. Emphasis is on the reaction dynamics and the yield of the intermediate ethanal using continuation and optimization techniques. We characterize regions of periodic, complex periodic, and chaotic oscillations. The chaotic region is reached by type III intermittency. In all cases, the global optimum yield of the intermediate is a steady state, which is unstable or stable due to the location of the stability boundary. It is found that autonomous periodic operation is only locally better than steady state operation. In the second part, different types of mass and energy coupling between two reactors are studied. The results obtained for a simple consecutive parallel reaction scheme are validated by a more detailed model of the ethanol oxidation by hydrogen peroxide under iron(III) catalysis, which can be described by an extended consecutive-parallel reaction scheme. Analogies are found with respect to the dynamics and the yield of the intermediate.