Chlor-Alkali Process

The chlor-alkali process is an industrial process that uses electrolysis to split a solution of sodium chloride, common salt, into chlorine gas and sodium hydroxide, or caustic soda, two of the chemical industry's most widely used raw materials. The English chemist William Cruikshank first demonstrated chlorine formation from electrolyzed brine around 1800, and Michael Faraday laid out the governing principles of solution electrolysis in 1833, but commercial-scale chlor-alkali production did not begin until 1892. The process runs the reaction two sodium chloride plus two water yields chlorine, hydrogen and two sodium hydroxide, with chloride ions oxidizing into chlorine gas at the anode while water splits into hydrogen gas and hydroxide ions at the cathode; modern plants use ion-selective membranes to keep the products from recombining, and global production had grown to roughly ninety seven million tonnes by 2022.