Desalination, Vol.228, No.1-3, 237-244, 2008
Desalting of neutral amino acids fermentative solutions by electrodialysis with ion-exchange membranes
The process of desalting of a proline modelling solution by electrodialysis in five- and six-chamber electrodialysis apparatus was investigated. It has been shown that the process effectively proceeded in the six-chamber device. Changes of dry substances and pH of the proline modeling solution and also voltage in a circuit in the course of the desalting process were determined depending on the current density. Kinetic curves of migration of proline through a CM-40 membrane in the desalting process have been registered and the optimum density of a current necessary to carry out the desalting process of proline solution has been determined. Kinetic curves of the proline Solution desalting have shown that in optimal and close to optimal areas of current density 99.3%, desalting of the proline solution was achieved, while with a current higher than optimal the degree of desalting of solution was about 94.6%. It was shown that the obtained relationships of the desalting process of the proline modelling solution were completely reproduced in permeate desalting during the chalk-free L-proline, L-valine and L-alanine fermentations. On the basis of the obtained results, it is possible to develop technologically accessible electrodialysis of amino acids as well as other biologically active substance desalting from cultured liquids.