Electrodeionization is used to prepare very pure water with a resistivity above 15 MΩ cm at industrial and laboratory scale. Electrodeionization (EDI) is an alternative separation process that replaces conventional demineralisation of water on a mixed bed of ion exchangers.

EDI benefits from the preferred electrochemical properties of the ion exchangers in the environment of low conductive solutions. Separation of ions and poorly dissociated components from water is achieved by the application of direct current.

The power consumption is low, usually 0.1 to 0.5 kWh / m3 of product. Unlike conventional technology, EDI is a continuous process that does not require interruptions due to the need for ion exchanger regeneration.