Applications for Chlor-Alkali Electrolysis

In membrane cell process, purified saturated brine is passed into the anode chamber of the cell where the Cl ions are oxidized at the anode, losing electrons to 

At the cathode, positive H+ ions pulled from water molecules are reduced by the electrons provided by the electrolytic current, to H2, releasing OH ions into the solution  

In addition to keeping CI2 and H2 gases separated, the ion-exchanging manbrane at the center of the cell prevents the unfavorable back migration of OH ions from cathode chamber, while allowing the Na+ ions to pass to the cathode chamber where they react with the OH ions to produce caustic soda (NaOH). The overall reaction 

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