The Electrodeionization method is actually a membrane process that is performed in order to undertake the post-purification step. In this process, the goal is to separate the ions dissolved in the wastewater from the aqueous feed and will be done with the help of a membrane. This method has provided significant assistance to the chemical and semiconductor industry by producing ultra-pure water from the wastewater received as feed. The process of electrodeionization is usually used to polish reverse osmosis (RO) process and the intensity of the penetration of undesirable factors into the membrane. Due to the fact that this method does not require storage and handling the toxic and hazardous chemicals, which are used for resin reproduction and waste neutralization, it can be considered a good alternative to ion exchange method in mixed beds.

In summary, in this method, several layers of selective membranes are placed between the cathode (negative electrode) and the anode (positive electrode). The chamber between these layers is either alternatively containing a mixed bed ion exchanger or used as a concentrate chamber. Water or sewage flows between the anode and the cathode; This selective membrane sends positive ions to the negative electrode and negative ions to the positive electrode, thereby separating. The result will be the production of high purity deionized water. The main difference between electrodeionization and other purification methods is that this method does not use chemical methods or packages to remove the undesirable contents.