MODELING AND SIMULATION OF CATALYTIC DISTILLATION COLUMN FOR THE ESTERIFICATION OF ACETIC ACID WITH ALCOHOLS

Abstract

The present study deals with the esterification reaction of acetic acid with alcohols viz. are methanol and butanol in the reactive distillation column. In the reactive distillation column where the reaction and the separation are done in a single column, the heterogeneous catalyzed reaction is considered. The catalyst used in the present study is Amberyst-15. First the mathematical modeling for the esterification of reaction of acetic acid with alcohols is done by writing MESH equations viz. Material balances, Equilibrium relationships, Summation relationships and Heat Balances. Then kinetics data for the esterification reactions for the acetic acid with methanol and with the butanol were taken from the literature. Thermodynamic model used was UNIQUAC and the interaction parameter were taken from the literature. With the help of kinetic data, the simulation for the above mentioned esterification reactions is done in ASPEN Plus V8.4. The results thus obtained were then verified with the data available in the literatures. After the verification of the two alcohols, the parametric study was carried out for the methanol with the two different feed set up – A column where the both the feeds are fed on a single stage and other where the two feeds are fed on two different stages. The parameter chosen were to investigate how the yield of the acetate and the conversion of alcohol in the esterification reaction can be increased. Reflux ratio, Reboiler duty, Feed stage location for the acetic acid and feed stage location for the methanol are the important parameters. Apart from these, start of reactive stage and end of reactive stage effect was also studied to determine the optimum number of reactive and non-reactive stage. Finally effect of the head pressure in the column, flow rates of the reactant to the column, temperature of the reactant entering into the column and various thermodynamic model is done for investigating the yield of methyl acetate and conversion of methyl alcohol.