Application of electrodialysis within fi

Several fine chemicals and pharmaceutical products are obtained by multi-step processes involving, amongst others, the neutralization of acid and basic solutions which lead to the formation of salts. This study investigates two routes using electrodialysis with bipolar membranes (EDBM): converting salts into corresponding acid and basic solutions, or neutralizing alkali salts of the required organic acid. The feasibility of both electrodialysis processes for amino acid production was evaluated within a European Research Program. The process focusing on conversion was deemed unattractive due to high amino acid loss and economic concerns. The second process was executed in batch mode at a fixed current density of 1000 A/m² until the stack voltage peaked at 30 V, after which acidification continued at constant voltage while decreasing the current density to 400 A/m². Current efficiency ranged from 85 to 97%. Technological aspects, including avoiding amino acid precipitation in the membrane stack and achieving maximum concentrations of the neutralized amino acids and basic solutions produced, were discussed. Future trials are planned in a larger-scale unit to improve stability and efficiency.