Model-Based Optimization of Semibatch Emulsion Polymerization of Styrene

Industrial & Engineering Chemistry Research, vol. 59, pp. 16368–16379

Abstract

Emulsion polymerization reactors usually operate under starved conditions to better control the polymer properties and keep a safe operation. The main drawback is the low productivity obtained. In this work, we optimize offline the flow rates for the semibatch emulsion polymerization of styrene under starved conditions and keeping the reaction under diffusion limitation in order to maximize the reaction rate. To achieve this, we impose the maximal concentration of monomer in the particles as a path constraint. This results in a higher reaction rate compared to starved conditions close to saturation. At the same time, it enables safe operation by avoiding accumulation of monomer that may react hazardously at the end of the reaction, once the gel effect occurs. Therefore, we show that high productivity can be obtained by operating the reactor under starved conditions. We compare the optimal recipe under diffusion limitations with the benchmark of keeping the concentration of monomer in the polymer particles close to saturation and with constant feeding flow rates. We find consistent improvement of both the average reaction rate and the amount of polymer produced in the optimized strategy.

Authors 4

1. Eduardo S. Schultz Aachen Process Systems Engineering (AVT.SVT)

   Lyon 1 Université · Centre National de la Recherche Scientifique · Université de Lyon · Laboratoire d'Automatique, de Génie des Procédés et de Génie Pharmaceutique · École d'Ingénieurs en Chimie et Sciences du Numérique · RWTH Aachen University

   Affiliation as printed

   Laboratoire d’Automatique et de Génie des Procédés (LAGEPP), CPE Lyon, CNRS, UMR 5007, Université de Lyon, Université Lyon 1, Villeurbanne, France

   Process Systems Engineering (AVT.SVT), RWTH Aachen University, Forckenbeckstrasse 51, 52074 Aachen, Germany

2. Nida Sheibat‐Othman

   Lyon 1 Université · Centre National de la Recherche Scientifique · Université de Lyon · Laboratoire d'Automatique, de Génie des Procédés et de Génie Pharmaceutique · École d'Ingénieurs en Chimie et Sciences du Numérique

   Affiliation as printed

   Laboratoire d’Automatique et de Génie des Procédés (LAGEPP), CPE Lyon, CNRS, UMR 5007, Université de Lyon, Université Lyon 1, Villeurbanne, France

3. Alexander Mitsos Aachen Process Systems Engineering (AVT.SVT)

   Jülich Aachen Research Alliance · RWTH Aachen University

   Affiliation as printed

   JARA-Soft, 52056 Aachen, Germany

   Process Systems Engineering (AVT.SVT), RWTH Aachen University, Forckenbeckstrasse 51, 52074 Aachen, Germany

4. Adel Mhamdi corresponding Aachen Process Systems Engineering (AVT.SVT)

   RWTH Aachen University

   Affiliation as printed

   Process Systems Engineering (AVT.SVT), RWTH Aachen University, Forckenbeckstrasse 51, 52074 Aachen, Germany