Abstract
The esterification of acetic acid with butanol catalysed by Amberlyst 15 was studied over a range of catalyst loadings, temperature, molar ratio of reactants, stirrer speed and particle size of catalyst. The equilibrium constant was experimentally determined and the reaction was found to be exothermic. Swelling and adsorption studies were performed to estimate the adsorption constants. The values found for the adsorption constants follow the order: water > butanol > acetic acid > butyl acetate. Experimental kinetic data for the esterification were correlated with the Pseudohomogeneous (PH), Eley-Rideal (ER) and Langmuir-Hinshelwood-Haugen-Watson (LHHW) models. The activity coefficients were calculated according to the UNIQUAC method. A possible mechanism of this reaction involved following the Eley-Rideal mechanism in which an adsorbed and protonated butanol molecule reacts with an acetic acid molecule in the bulk. The activation energy of the forward reaction was found to be 45.4kJ mol−1.