Dynamic optimization of semibatch vinyl acetate/acrylic acid suspension copolymerizations

Abstract

This work performs the dynamic optimization of semibatch vinyl acetate (VAc)/acrylic acid (AA) suspension copolymerizations. The proposed dynamic optimization strategy is based on a direct search Complex algorithm and is used to control the copolymer composition along the batch. First, a sequential optimization procedure is used to determine the optimum AA concentration and feed rate profiles, required to provide the specified copolymer composition. In the second step, a sequential optimization procedure is coupled with a predictive controller to guarantee that the manipulation of feed flow rates can allow for attainment of the desired copolymer compositions. The optimization strategy is validated through simulation, by assuming that reactions are subject to perturbations of the reaction temperature, initiator, and VAc concentrations. It is shown that the proposed optimization strategy can be used successfully both for design of monomer feed rate profiles and removal of process disturbances during semibatch suspension copolymerizations, to keep the copolymer composition constant throughout the batch.

Drug Micro-Carriers Based on Polymers and Their Sterilization

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“…For the parameter estimation task, it is required that a set of ordinary differential equations be solved iteratively as a dynamic optimization problem (Machado et al, 2010, Soares et al, 2011. In this scenario, direct search methods (N.B.…”

“…In this scenario, direct search methods (N.B. Figure 1 shows the parameter estimation procedure adopted here based on a standard sequential optimization procedure (Machado et al, 2010, Soares et al, 2011, which is responsible for the determination of an optimum solution that has to satisfy the process model represented by Eqs. According to Machado and co-authors (2010), the use of the Complex optimization technique is strongly recommended when the optimization task is carried out using a large system of differential equations.…”

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