Experimental and Simulation Studies of Industrial Scale Finishing Reactive Distillation Column

Abstract

RD is the process developed by integrating two different operations (chemical reaction and multi-stage distillation) simultaneously in a single unit. Reactive distillation (RD) has been successfully implemented for the production of the Ethyl acetate (EtAc).The RD feature of shifting the equilibrium in the forward direction is useful for EtAc production by the reversible esterification reaction of acetic acid with ethanol. The main advantages of using the RD with a pre-reactor for the production of the EtAc is that, the existing plants based on the conventional process can be easily revamped to use the RD technology. Also, in case of RD with pre-reactor, a smaller RD column (as compared to complete RD process) is required which reduces the capital investment. At IOL Chemicals and Pharmaceuticals Ltd., the EtAc is produced by the esterification of HAc with EtOH in the presence of the homogeneous acid catalyst (para-toluene-sulfonic acid) using RD with pre-reactor. Most of the reaction takes place in the reactor and the reacted mixture is fed to the column where simultaneous removal of product improves the conversion and product yield. The work reported in this thesis was aimed at generating the experimental data from an industrial scale RD column (situated at IOL Chemicals and Pharmaceuticals Limited, Trident Complex, Barnala, Punjab, India) and to compare the simulation results with this RD column data. The provision for the collection of vapor and liquid samples from each tray was made during a scheduled shutdown of the plant. The simulation was carried out using the rate based model of Aspen PlusTM, as the column hardware information was readily available. A new set of thermodynamic parameters for the NRTL model was established for the highly the non-ideal liquid mixture, of this reaction system, by regression of the vapor-liquid equilibrium data available in literature. Predicted vapor and liquid composition profiles are in good agreement with plant data.