Reaction Kinetics for Reactive Distillation Using Different Laboratory Reactors

The reaction kinetics of the heterogeneously catalyzed esterification of n -hexyl acetate were measured using both a batch reactor and continuous stirred tank reactor (CSTR). The catalyst was Amberlyst CSP2. The results of the batch reactor and CSTR experiments were compared to reaction kinetic measurements carried out in previous work using a plug-flow reactor (PFR). Because the change in the composition of the reaction mixture in the batch reactor is caused not only by reaction but also by component-specific adsorption on the catalyst, the batch reactor is not recommended for reaction kinetic measurements of the present type of chemical system. The results from the CSTR and PFR are in very good agreement with regard to the measured rate of reaction. To address the impact of the conditions present in a heterogeneously catalyzed reactive distillation (HCRD) column on the performance of the catalyst, the influences of boiling and of the reduction of the low-boiling components (here, water) on the rate of reaction were investigated using the CSTR. Neither was found to have a significant impact on the performance of the catalyst. A simple pseudohomogeneous model was fitted to the data of the CSTR experiments using a reparameterized Arrhenius equation to avoid parameter coupling. The model predictions and experimental results are in good agreement.