Technology Type

The Chlor-Alkali Electrolysis Process is used in the Manufacture of Chlorine, Hydrogen, and Sodium Hydroxide (Caustic) solution. Of these 3, the primary Product is Chlorine. There are 3 types of Electrolytic Processes used in the Production of Chlorine:

1. the Diaphragm Cell Process,
2. the Mercury Cell Process, and
3. the Membrane Cell Process.

In each Process, a Salt Solution is electrolyzed by the action of direct electric current that converts Chloride Ions to Elemental Chlorine. The overall Process Reaction is:

2 NaCl + 2 H₂O → Cl₂ + H₂ + 2 NaOH

In all 3 methods, the Chlorine (Cl₂) is produced at the Positive Electrode (Anode) and the Caustic Soda (NaOH) and Hydrogen (H₂) are produced, directly or indirectly, at the Negative Electrode (Cathode). The 3 Processes differ in the method by which the Anode Products are kept separate from the Cathode Products.