Classification of ion exchange membranes

Ion exchange membranes are classified in various ways based on their functions materials constituting the membranes structure and microstructure of the membranes, etc. However, classification based on the function is clear because the function of the ion exchange membrane is determined by the species and charge of the ion-exchange groups fixed in the membranes, positive and/or negative, and their distribution in the membrane. 

cation exchange membranes, which have cation exchange groups (anionic charged groups), and cations selectively permeate through the membranes, 

amphoteric ion exchange membranes, in which there are both cation and anion exchange groups at random throughout the membranes, 

bipolar ion exchange membranes which have a cation exchange membrane layer and anion exchange membrane layer (bilayer membranes), 

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