Sorption of acidic impurities from diethyl phthalate and butyl acetate using basic resins, bearing tertiary amino groups on a styrene-divinylbenzene macroporous matrix, has been investigated for purification of the esters. The equilibrium Studies show selective sorption of the acidic impurities and a high loading capacity (in the range of 2.2-5.3 mol/kg of dry resin) even at millimolar acid concentrations. The uptake of the acids is assisted by specific Lewis acid-base interaction with the functional group of the resins. The interaction leads to formation of a hydrogen bonded complex between the acidic proton and the lone pair of electrons on the nitrogen of the amino group. The sorption Studies have also been performed in ethanol and butyl alcohol to evaluate their use for the regeneration of the resins and recovery of the acids. The sorption data have also been analyzed using extended Flory-Huggin theory of polymer solutions to determine the interaction parameters between different components.