Chemical Engineering and Processing, Vol.70, 117-130, 2013
A reactive distillation process with a sidedraw stream to enhance the production of isopropyl acetate
This paper designs an entrainer combined with a sidedraw to enhance the reactive distillation (RD) process of isopropyl acetate (IPAc). Acetic acid (HAc) reacts with isopropanol (IPOH) to generate IPAc and water (H2O). The ratio of IPAc to H2O in the products of esterification is smaller than that in the minimum boiling IPAc-IPOH-H2O azeotrope, resulting in a mass of organic phase reflux to remove the surplus H2O from the top of the RD column. This process consumes a high amount of energy. For better energy efficiency, a feasible design flowsheet includes an RD column, a stripper, a top decanter, a middle decanter, and a sidedraw stream to intensify the azeotropic separation where an entrainer is introduced to carry out the surplus water from the middle of the RD column in the form of a liquid phase. The key design variables in the proposed flowsheet are determined to obtain a minimal total annual cost (TAC). As a result, an optimal process design is drawn out while satisfying the stringent specifications for product purity. These results show that the energy requirements of the IPAc system can be decreased by 27.55%. Crown Copyright (C) 2013 Published by Elsevier B.V. All rights reserved.