Constrained optimization for fine chemical productions in batch reactors

Abstract

Batch and semibatch reactors are the main device of batch processes which are still widely used to produce pharmaceuticals, polymers, biotechnologicals etc. Fine chemical transformations are characterized by quite complex reaction systems which can produce undesirable end products. As the aim of the fine chemical industry is to produce high quality and purity products, it is essential to optimize batch operating conditions, i.e. temperature profile, feed flow rate, amount of reactant and final batch time, taking into account constraints on the experimental feasibility (heating and cooling rates) or the specificities of fine chemistry productions (purity constraints, …). In this work, the optimal control problem is converted into a non-linear programming problem solved by the generalized reduced gradient procedure coupled with the golden search method, for the search of the total batch time. The efficiency of the methodology is shown by its application to different formulations of the problem for different chemical reaction schemes and with stress laid on the influence of the constraints on the limitation of temperature variations and byproduct formation.