How is chlorine produced?

Chlorine is produced by passing an electric current through a solution of brine (common salt dissolved in water). This process is called electrolysis. The chemical term for salt is sodium chloride (NaCl). NEW: download the production process animations (see below).

Essential co-products are caustic soda (sodium hydroxide or NaOH) and hydrogen (H₂). All three are highly reactive, and technologies have been developed to separate them and keep them apart. Caustic soda is an alkali and widely-used in many industries, including the food industry, textile production, soap and other cleaning agents, water treatment and effluent control.

See the uses of caustic soda page

Hydrogen is a combustible gas used in various processes including the production of hydrogen peroxide and ammonia as well as the removal of sulphur from petroleum derivatives in order to avoid the emission of acid fumes in their combustion gases.

Chlorine has been manufactured industrially for more than 110 years now.
See the uses of chlorine page to learn much more about applications of chlorine.

The three main technologies of producing chlorine are

• the membrane cell process, nowadays most widely used in Europe,
• the mercury cell process, being phased out worldwide because of the toxic character of mercury and
• the diaphragm cell process.

Click on the process names above to visualize the animations (turn sound on) and download print copies of the diagrams. 

NEW:

send us an e-mail and we will grant you access to downloadable versions of these chlorine production process animations! Use them in your classrooms!

Publishing these animations on a website is only allowed if you mention:
source www.eurochlor.org. 

Please send us a link if you posted the animations on a website.

Last update: 04/2012