The esterification reaction is reversible and has low yield. In order to increase the yield of reaction, it is required to simultaneously remove the product of reaction. For this membranes are the viable approach. Pervaporation membranes have success in removal of components in dilute forms. Membrane performance is represented in terms of flux, sorption coefficient, separation factor, and permeance. These factors are related to the thickness of membrane, temperature, and feed concentration. Higher flux is observed at lower membrane thickness and higher feed concentration of water and lower selectivity is observed at higher temperatures due to increased free volume, lower viscosity, and higher feed side pressure. Different factors affect the pervaporation aided esterification reactor setup such as effect of initial molar ratios of the reactants, effect of catalyst concentration, effect of membrane area, and effect of temperature. Large membrane size could provide higher surface for the transfer of acid, though the challenges of membrane rupture do surround the studies. In the present review work, we tried to collaborate the works in totality of the pervaporation design starting from the membrane behavior to the process behavior. Different prospective fields are also explored which need investigation.

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Esterification of acrylic acid with ethanol, catalyzed by sulfuric acid has been carried out in stirred batch reactor under atmospheric pressure. Different parameters such as effect of initial molar ratios of the reactants, effect of catalyst concentration, initial water and effect of temperature has been studied in the batch reactor. Different catalyst loading system (1–3 vol%), reaction temperatures (50–70 °C), initial reactants molar ratio (1:1–1:3) and water concentration in feed (0–20 vol%) was used in the reaction system. The temperature dependence is exponential and expressed by Arrhenius type of relationship. Kinetics parameters such as equilibrium constant, rate constants, activation energy and reaction enthalpy and entropy were estimated by experimental data. The rate equation has a remarkable fit to the data and was able to describe the behavior of the system at various reaction temperatures. Hydrochloric acid (HCl) and hydro iodic acid (HI) were also compared with sulphuric acid as catalyst for esterification of acrylic acid with ethanol. Sulphuric acid was found to be more efficient catalyst for esterification as it induces the maximum conversion of acrylic acid.

Kinetics of esterification of acrylic acid with ethanol in the presence of homogeneous (H2SO4, HCl, p‐TSA, HI) catalysts as well as heterogeneous catalysts (Dowex 50WX, Amberlyst 15) was studied. The effects and performance of these catalysts on the conversion of acrylic acid were evaluated. In the kinetics of homogeneous catalyzed reaction, both concentration and activity‐based model were employed. Activity coefficients were predicted by the Universal Functional group Contribution (UNIFAC) method to consider nonideal behavior of the liquid phase. The heterogeneous catalyzed reaction mechanisms were developed using Eley–Rideal theory. The model results were compared with the experimental results and were in good agreement. The temperature dependency of the constants, reaction enthalpy, and entropy, and activation energy were determined. The conversion of acrylic acid was obtained as 63.2%, 61.02%, 53.3%, 21.4%, 34.96%, and 14.84% for H2SO4, p‐TSA, HCl, HI, Dowex 50WX, and Amberlyst 15, respectively, under process temperature of 70°C, reactant molar ratio of 1:1, and catalyst concentration of 2% (v/v) for homogeneous and 2.17 g for heterogeneous catalyst. These outcomes provide an approach to understand the significant effect of each catalyst on the esterification kinetics of acrylic acid and ethanol.