Liquid-liquid Equilibria (LLE) of the quaternary mixture (acetic acid + ethanol + ethyl acetate + water) arising out of esterification reaction: Optimization studies

The kinetics of esterification of acetic acid with ethanol over a heterogeneous catalyst, Dowex 50wx8-400 catalyst (hydrogen ion based catalyst), was performed in an isothermal batch reactor. Influence of different operating parameters, such as, effect of temperature (40 to 70 °C), catalyst loading (0.6 g to 1.5 g), initial molar ratios of acetic acid and ethanol (1:1 to 1:4), were studied. Conversion as high as 83% have been obtained. The activation energy of esterification of acetic acid with ethanol using Dowex 50 Wx8-400 was found to be 30.02 kJ mol− 1. The experiment results of the esterification reactions were correlated with pseudo - homogeneous (PH) model. Furthermore, an activity-based kinetic model for quaternary system (Acetic acid + Ethanol + Ethyl acetate + Water) was developed and correlated using the UNIQUAC (universal quasi-chemical equation) and NRTL (Non random two liquid) model to compute the activity coefficients. Response surface methodology (RSM) was employed to investigate the non linear dependency of operating parameters on the obtained response (ethyl ester conversion).