Analysis of volume and solute fluxes in separation of amino acids using a negatively charged membrane under pressure gradient.

Abstract

The separation of amino acids from aqueous solutions was performed using sulforrated polysulfone membrane at various pH values under a pressure gradient. The volume flux and the solute flux were measured under conditions where amino acids dissociated. With increasing concentration of amino acid in the feed solution, the solute flux increased and the volume flux decreased. The effective charge density of the membrane was determined from measurement of the membrane potential. By applying the proposed friction model incorporated with the effective charge density and the degree of dissociation of amino acid, the basic equations of volume flux and amino acid ion fluxes were derived. The effects of the concentration of amino acid and pH in the feed solution on the volume flux and the solute flux were analyzed on the basis of these equations, and the friction parameters were evaluated.