Resumen
Electrodialysis (ED) is a process which is to transport anions and cations selectively and remove them from solutions and concentrate to the other ones. In three-compartment electrodialysis it is possible to immobilize required ions in certain ED compartment and change their counterions. In laboratory electrodialysis unit sodium lactate model solution was tested for conversion onto lactic acid via ion substitution. Four different arrangement of streams and membrane arrangement were compared in membrane stack the process was described. Mole and mass flux, reached product purity and energy consumption were evaluated for all examined cases.