Esterification Catalyzed by Macroreticular Ion Exchange Resin in Strong Acid Form

Abstract

The esterification of n-fatty acids with 1- and 2-butanols catalyzed by macroreticular sulfonated ion exchange resin has been studied in a batch reactor. The reaction was first-order in concentration of fatty acid over the range of experimental conditions.From the results summarized in Figs.-2 and 3, it was determined that neither bulk diffusion nor pore diffusion is a limiting step in the reaction.The results of Fig.-4 show that in the esterification with 1-butanol catalyzed by the ion exchange resin the carbon number of fatty acid influences significantly the reaction rate, in other words the ion exchange resin as catalyst has selectivity. However, as may be seen in Fig.-5, in the esterification with 2-butanol the selectivity of the catalyst was not recognized. The above results are explained by introducing the assumption that the reaction with 1-butanol is catalyzed by the hydrophobic proton and the matrix-bound -SO3H groups, the reaction with 2-butanol is catalyzed by the hydrophobic proton and hydrated proton in the resin matrix.