Kinetics of mixed succinic acid/acetic acid esterification with Amberlyst 70 ion exchange resin as catalyst

Liquid phase esterification of succinic acid, acetic acid and succinic/acetic acid mixtures with ethanol was studied using Amberlyst 70 strong cation exchange resin as catalyst. Batch isothermal reactions were performed at different ethanol:acid molar ratios (1:1-27:1), temperatures (343-393 K) and catalyst loadings (1.0-9.3 wt% of solution). Esterification kinetics is described using both pseudo-homogeneous mole fraction and NRTL-based activity based models that take ethanol dehydration to diethyl ether into account. The models accurately predict the esterification of individual acids, and a simple additive combination of independent kinetic models provides a good description of mixed acid esterification. The kinetic models can be used in simulation of reactive distillation processes for mixed acid esterification. (c) 2012 Elsevier B.V. All rights reserved.