OPTIMIZATION OF THE REACTION CONDITIONS FOR COMPLEX KINETICS IN A SEMIBATCH REACTOR

Optimization of the reaction conditions in liquid phase semibatch reac tors where several complex reactions simultaneously take place was stu died. The optimization procedure was demonstrated with the production of substituted alkyl phenols from aromatic sulfonic acid via alkali fu sion. The reagent, the substituted aromatic sulfonic acid, participate s in the main reaction and in several side reactions, such as the elim ination of the alkyl, the amino, and the sulfonic acid groups as well as polymerization reactions. The kinetics was determined for the react ion system, on the basis of the laboratory scale batch reactor experim ents. The kinetic model was combined with a large scale reactor model, where not only the feed of the reactant but also the precipitation an d volatilization of some reacting compounds were considered. It turned out that, an extrapolation from the 0.1 dm(3) laboratory reactor to t he 10 m(3) large scale was very successful. The reaction conditions of industrial scale semibatch reactor were optimized using the desirabil ity function approach, which combines the desired conversion of the re agent, the desired selectivity of the product, and the reaction time. The qualities of different desirability functions were compared. The g reat benefit of the desirability approach is that it provides smooth o bjective functions, avoiding a cumbersome constrained optimization.