Extended rate-based model validation for polyester synthesis by reactive distillation

The state of the art equilibrium and rate-based models for reactive distillation (RD) are well developed and have been used for a couple of decades. However, these models are not sufficient to represent a kinetically controlled process. This shortcoming is due to neglecting the effect of liquid back mixing (LBM). In earlier work,. ¹ we have extended the rate-based model to account for LBM. The extended rate-based model clearly demonstrated significant improvements on the prediction of process description as compared to the traditional rate-based model. In this work, the extended rate-based model is validated experimentally in order to quantify the gained improvements. The experiments were performed for the kinetically controlled polyester synthesis in a reactive distillation pilot column. The predictions of the extended rate-based model - in terms of acid value, conversion, isomerization and saturation fraction, number-average molecular weight and degree of polymerization - are in very good agreement with the experimental data obtained from the reactive distillation pilot plant.