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The transesterification of methyl acetate and 1-hexanol catalyzed by the cation exchange resin Amberlyst-131 was studied to obtain optimum operating parameters, adsorption parameters, and kinetic parameters. The effects of temperature, molar ratio of ester to alcohol, stirrer speed, and catalyst loading on the reaction rate were investigated. The chemical equilibrium constants were obtained from kinetic experiments and theoretically from standard thermodynamic properties at temperatures of 333, 338, 343, and 348 K. The experimental data were tested with the pseudohomogeneous and adsorption based models. The activity coefficients were estimated using UNIQUAC to account for the nonideal thermodynamic behavior of reactants and products for both models. The activation energy for the transesterification reaction was found to be 37.8 kJ mol–1 by the Langmuir–Hinshelwood–Haugen–Watson (LHHW) model, which correlates the experimental data.

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The kinetics of the esterification of acetic acid with butanol in the presence of sulfated zirconia was studied. Several kinetic models were tested to correlate the kinetic data. The experimental data was represented by the Eley-Rideal mechanism and it is found that sulfated zirconia is suitable for this reaction since the activation energy reduced from 58.0 to 49.2 kJ/mol. The liquid phase esterification of butanol with acetic acid was carried out in a batch reactor at temperatures of 328, 333, 338 and 343 K, with an alcohol to acid molar ratio of 1. The equilibrium constants were determined in separate experiments at 328, 333, 338 and 343 K and calculated as 29.9, 29.3, 28.6 and 28.0, in order. Before these kinetic and equilibrium runs, the catalyst was prepared by impregnating zirconia with H 2 SO 4 . The prepared catalyst was characterized by thermal analysis, XRD, SEM, BETsurface area and IR analysis.

The liquid phase esterification of acrylic acid with different alcohols (butanol, iso-butanol, or hexanol) was investigated in a batch reactor with zirconia supported tungstophosphoric acid (TPA) as heterogeneous catalyst. The prepared catalysts with different TPA loadings (20, 25, and 30 wt %) and calcination temperatures (550, 650, and 750 °C) were characterized by nitrogen adsorption studies, X-ray diffraction (XRD), and thermogravimetric analysis (TGA) techniques. In addition, acidity measurements were performed by potentiometric titration with n-butylamine. The activitiy of catalysts strongly dependent on the acidic characteristic of the catalysts. The most active catalyst, 25 wt % TPA, calcined at 650 °C, gave more than 33%, 31%, and 27% conversions of acrylic acid for butyl, iso-butyl, and hexyl acrylate synthesis, respectively.