The role of the ionic form of the ion exchanger at the non-exchange sorption of phenylalanine

Abstract

For identification of features of fixing of substances in the ion exchanger at not exchange sorption, and also the choice of optimum conditions for division of multicomponent mixes, it is necessary to investigate various ionic forms of a sorbent. The non-exchange sorption of phenylalanine from aqueous solutions by anion exchanger AV-17-2P in different ionic forms: similar (F^-, Сl^-, Br^-, I^-) and different (Сl^-, ОН^-, NO₃^-, Phe^-) is considered.

In water solution phenylalanine is present at a type of bipolar ions, and use of the anion exchanger in a salt form excludes a recharge and ion-exchange fixing of amino acid, thus, in system not exchange absorption proceeds. Isotherms of sorption of phenylalanine on the AV-17-2P anion exchanger in various ionic forms are received and discussed. Influence of a mitselloobrazovaniye of phenylalanine in solution by sight of isotherms and amino acid absorption size is considered. It is shown that on the AV-17-2P anion exchanger in the ionic forms which are characterized by good swelling, the mitselloobrazovaniye in solution has no significant effect on a type of isotherms and size of sorption of phenylalanine. In work influence of various amount of water in a phase of a sorbent, ability to hydration, the size, geometry, density and localization of a charge on interpartial interactions in a sorbent phase is discussed at not exchange sorption of phenylalanine by the AV-17-2P anion exchanger.

It is revealed that when using a sorbent with the antiion of one nature (halogenide ions) determining by a factor at sorption hydration of an antiion is. When using OH- forms of a sorbent occurs change of the mechanism of absorption of phenylalanine as in a phase of an ionite the recharge of a bipolar ion of amino acid in anion and electrostatic interaction with functional group proceeds, i.e. ionic exchange with a recharge proceeds.   When using the anionit in ionic forms of various nature sorption is defined by a structure of an antiion and its ability to additional interactions, up to change of the mechanism of absorption. Increase in the size of an antiion promotes deterioration in sorption of amino acid, and increase in hydration and additional hydrophobic interactions with an antiion in a sorbent promote the best sorption of the tsvitterlit.