IR Spectroscopic Study of the Mechanism of Phenylalanine Sorption from Aqueous Solutions by a Shaped Sulfonic Acid Cation-Exchange Membrane with a Styrene-Divinylbenzene Matrix

The mechanism of phenylalanine absorption by a shaped sulfonic acid cation-exchange membrane with a styrene-divinylbenzene matrix was studied by IR spectroscopy. An analysis of the results of the IR spectroscopic studies showed that the interaction in the sorbent-sorbate system is based on ion-exchange sorption via protonation with addition of the hydrogen counterion to the carboxyl group of amino acid and ion exchange with displacement of the hydrogen ion into the equilibrium solution. The occurrence of nonexchange sorption due to the additional interparticle interactions characteristic of the aromatic amino acid of phenylalanine was proven by sorbate association in the polymer material.