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Which products are made during chlorine-alkali electrolysis?

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A labeled diagram of the chlorine element from the periodic table shows its atomic number 17, symbol Cl, electron configuration, and atomic weight range. The box is shaded green to indicate chlorine is a halogen, with icons for orthorhombic crystal structure, gas state at room temperature, and strong acidity. A key explains the icons and colors used. — chlorine Properties of chlorine.

Chlorine-alkali electrolysis (also known as the chlor-alkali process) is an industrial electrochemical method that produces three primary products simultaneously through the electrolysis of brine (a concentrated solution of sodium chloride):

Chlorine gas: Produced at the anode.12
Hydrogen gas: Generated at the cathode.12
Sodium hydroxide (caustic soda): Produced in the electrolyte solution.123

In this process, the electric current causes the decomposition of sodium chloride and water. Because chlorine and sodium hydroxide react if they come into contact, industrial cells—such as the diaphragm cell or the mercury cell—are designed to keep these products separated during production.12