Premium
Thermodynamic modeling of multicomponent ion‐exchange equilibria of amino acids
Author(s) -
Bellot Jean Christophe,
Tarantino Ramon Vega,
Condoret JeanStéhane
Publication year - 1999
Publication title -
aiche journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.958
H-Index - 167
eISSN - 1547-5905
pISSN - 0001-1541
DOI - 10.1002/aic.690450617
Subject(s) - chemistry , thermodynamics , unifac , aqueous solution , activity coefficient , ion exchange , phase (matter) , chromatography , ion , organic chemistry , physics
A thermodynamic model was developed to describe phase equilibria for aqueous amino acid/polyelectrolyte gel systems. In the gel phase, activities of all exchangeable species (charged and neutral components) are calculated with the generalized Flory‐Huggins model. In the surrounding solution, a numerical procedure is used to allow for partial dissociation phenomena combined with a modified UNIFAC model associated with the Pitzer‐Debye‐Hückel term. The osmotic pressure difference between the two phases is also taken into account in the equations. The model enables the prediction of resin‐phase composition, gel swelling and intraparticle pH. It can be used for various biochemicals in a wide range of concentrations. Its validity was successfully tested using binary and multicomponent exchange equilibria data of several amino acids (phenylalanine, alanine, proline, and glutamate) and HCl on a strong‐acid cation‐exchange resin (Amberjet 1200H).