Liquid-phase esterification of acetic acid with isobutanol catalyzed by ion-exchange resins

Esterification of carboxylic acids with alcohols represents well-known liquid-phase reactions of considerable industrial interest due to the importance of organic ester products. These ester products include environmentally friendly solvents, flavors, pharmaceuticals, plasticizers, and cosmetics. In this study, the esterification kinetics of acetic acid with isobutanol in 1,4-dioxan as a solvent without adding a catalyst and catalyzed by ion-exchange resins are carried out using a batch reactor. The effect of catalyst type, stirrer speed, the effects of reaction temperature and catalyst loading on the initial reaction rate, the effect of speed of agitation and the conversion of acetic acid versus time were investigated. The kinetics of heterogeneous catalyzed esterification of acetic acid with isobutanol was correlated by a kinetic model based on pseudo-homogeneous catalysis. The strong acidic cation exchange resins were used as solid catalysts, Dowex 50 Wx2, Amberlite IR-120, respectively. As a result, it was found that the weight-based activity of the heterogeneous catalysts increases in the following order: Dowex 50 Wx2 > Amberlite IR-120 and these catalysts were effectively for the synthesis of isobutyl acetate under these experimental conditions. (c) 2007 Elsevier Ltd. All rights reserved.