(428d) Reactive Distillation Column for Esterification of Lauric Acid with Methanol: Equilibrium Vs. Nonequilibrium Approaches

Esterification of lauric acid with methanol in catalytic reactive distillation using solid catalyst reduces operation cost by combing reaction and separation zones into a single vessel [1]. Reactive distillation consists of separation zone and the reaction zone, and enhances the overall performance of the column, such as decreasing waste and overcoming thermodynamic and chemical equilibrium limitations [2]. A super-acid sulphated zirconia catalyst exhibit similar acidic property comparable to sulfuric acid (H2SO4) is most suitable candidate for reactive distillation application. However, high content of water in the reaction zone causes liquid-liquid separation leading to solid catalyst deactivation. In this study, we proposed a novel approach that effectively removes water. The distillation column operations at equilibrium and rate-based are compared and discussed. The simulation involved the sensitivity analysis to two key parameters, molar reflux ratio and side reboiler, on the water concentration in the reactive zone and ester purity in the product stream in both designs. Correct placements of side reboiler not only remove water effectively, but also enhance conversion rate by increasing the reaction zone temperature and reduce exergy loss considerably.

1. Kenig, E.Y., Gorak, A., Pyhalahti,A., Jakobson, K., Aittamaa, J., Sundmacher, K., Advanced rate-based simulation tool for reactive distillation, AIChE 50 (2004) 322-342. 2. Demirel, Y., Thermodynamic Analysis of Separation Systems, Separation Sci. Technol. 39 (2004) 3897-3942.