Caustic soda, with its co-product chlorine, is produced via an electrolysis of brine, in the ratio of one part chlorine to 1.1 parts caustic soda. Chlor-alkali products can be manufactured using one of three processes – mercury, diaphragm and membrane, with the industry moving towards the membrane process.
Typically chlor-alkali manufacturers use a proportion of their chlorine captively, as it is used in the production of a considerable number of chemicals. The most important of these is vinyl chloride, which accounts for around a third of chlorine consumption. Other end uses include solvents, water treatment and inorganic pigments. Even the intermediates used to make chlorine-free products contain chlorine.
The largest end markets for caustic soda are the alumina industry (13%), mining, organic chemicals (18%), inorganic chemicals (11%) and pulp and paper (16%). Other important end uses include textiles (10%) and soaps and detergents (8%). In chemical manufacturing, caustic soda is used for pH control, acid neutralisation and as a catalyst.
ICIS pricing quotes caustic soda in Europe, Asia-Pacific, US Gulf, Latin America, Africa and China.
To find out more Caustic Soda Methodology June 2013