Kinetics behavior of esterification of acetic acid with methanol over Amberlyst 36

The kinetic behavior of heterogeneous esterification of acetic acid with methanol over an acidic cation-exchange resin, Amberlyst 36, was investigated by using a packed-bed reactor. The kinetic experiments were conducted at temperatures from 313.15 K to 328.15 K and the molar ratios of methanol to acetic acid in the feed stream from 1 to 5. The reaction rate was found to increase with increasing temperature, but the equilibrium conversions of acetic acid changed slightly over the entire range of reaction temperatures. It is suggested that the heat effect of this reaction is negligible over the experimental conditions. It was also found that the equilibrium conversion of acetic acid increases with the molar ratios of feed increasing from 1 to 5. The relative adsorption strength between any two reacting species was determined from the results of binary adsorption experiments. The magnitude of adsorption strengths follows the order of water > methanol > acetic acid > methyl acetate. The kinetic data were correlated with the ideal-quasi-homogeneous (IQH), the nonideal-quasi-homogeneous (NIQH), the Eley–Rideal (ER), and the Langmuir–Hinshelwood–Hougen–Waston (LHHW) models, respectively, to determine the kinetic parameters. Among these investigated models, the ER and the LHHW are equally well and obviously better than IQH model.

► Kinetic behavior of acetic acid with methanol over Amberlyst 36 has been studied.
► Adsorption strengths: water > methanol > acetic acid > methyl acetate.
► The ER and the LHHW models correlated satisfactorily the kinetic data.