MULTICOMPONENT ADSORPTION EQUILIBRIA OF AMINO ACIDS ON POLYMER RESINS

摘要

Amino acids are widely used in many fields such as food, chemical, pharmaceutical, agricultural, medicine and cosmetic industries and are mainly produced by microbial fermentation. To improve the efficiency of recovery, separation, and purification from fermentation broths, several separation techniques have been employed. When the energy efficiency, selectivity, and cost are considered, the adsorption-based separation technique is a promising method for the separation of the amino acids. Several studies have been reported in the literature for amino acid adsorption on various materials including activated carbon, silica, ion exchangers, alumina and polymeric resins. Of these, polymeric sorbents are more attractive because of their regeneration characteristics and have been extensively used for the removal of organic contaminants from dilute aqueous mixtures and air streams and also for the recovery of biochemicals from dilute liquid solutions. The main objective of the present study was to acquire accurate information on adsorption and desorption behaviors of amino acids on polymeric sorbents, XAD-4 and XAD-16. Desorption can be assumed to be a competitive adsorption between an amino acid and a desorbate. In order to confirm this postulate, several binary equilibrium data between amino acids and organic solvents were obtained and compared with predicted results. For calculation, Extended Langmuir (EL) and Ideal Adsorbed Solution Theory (IAST) based on the Langmuir equation as a single-component isotherm were employed to represent the competitive adsorption equilibria.