Thermochemical kinetics of the formation of supramolecular compounds of amino acids with carboxylic cation exchangers

The kinetics of sorption of glycine and methionine from aqueous solutions with various acidities on the carboxylic cation exchangers KB-2 and KB-4 in protonated, deprotonated, and copper forms at 298 K was studied by microcalorimetry. In the sorption of the amino acids on the copper forms of the cation exchangers, the heat flux changes its sign. The character of the aliphatic amino acid-carboxylic cation exchanger interparticle interaction depends on the ionic form of the cation exchanger. As determined by the sorption method and IR spectroscopy, the nature of the glycine and methionine sorption sites in the ion exchanger phase changes on passing from the protonated to the copper form of the sorbent.