Esterification of propionic acid with isopropyl alcohol over ion exchange resins: Optimization and kinetics

The esterification of propionic acid with isopropyl alcohol was studied in an isothermal batch reactor. The activities of three different types of ion exchange resin catalysts (Amberlyst 15, Amberlyst 70 and Dowex 50 WX8) were investigated, and Amberlyst 15 was found to be an effective catalyst for the reaction. The effects of process parameters, namely, catalyst loading, alcohol to acid molar ratio and reaction temperature, were studied and optimized. Response surface methodology (RSM) was applied to optimize the process parameters as well as to investigate the interaction between process parameters. The internal and external diffusion limitations were found to be absent at a stirring speed of 500 rpm. The RSM model predicted response (83.26%) was verified experimentally with a good agreement of experimental value (83.62±0.39%). Moreover, the kinetics was studied and the Langmuir-Hinshelwood model was used to fit the kinetic data.