Design of a Complete Ethyl Acetate Reactive Distillation System

Abstract

In this paper, design of a complete reactive distillation (RD) system has been developed. The reactive distillation system in the study is the production of ethyl acetate (EtAc) via esterification of acetic acid (HAc) with ethanol (EtOH) using sulphuric acid as homogeneous catalyst. A suitable NRTL model parameter set for calculating of liquid activity coefficients has been established with excellent prediction of the compositions and temperatures for the four azeotropes in this system. In the VLE calculations, vapor association of acetic acid due to dimerization has also been considered. A reactive distillation column with an overhead decanter can be designed to achieve over 93 wt% of ethyl acetate composition at organic phase top product stream while the bottom product stream is designed to be rich in acetic acid so that it can be recycled and mixed with fresh acid make-up stream to serve as acid feed to the reactive distillation column. Since the purity of the optimum top organic product is still not good enough for the ethyl acetate product specification in industry, an additional column is designed to purify the ethyl acetate product of the reactive distillation column to over 99.5 wt%. The top draw of the second column will be recycled back to the decanter. In summary, the overall optimum design of this ethyl acetate reactive distillation system includes two columns (including the reactive distillation column and the second column), one decanter, and two recycle streams. The optimum operating condition of the overall system will also be studied to minimize the total operating cost of the overall system while meeting product specifications.