Caustic soda


Caustic soda is an important inorganic chemical produced by the electrolysis of salt (or less commonly from natural deposits of soda ash on reacting with lime). World production of caustic soda is about 45 million tonnes used to produce a broad range of inorganic chemicals and used in general manufacturing, mineral processing and water treatment.


The main applications of caustic soda include production of alumina.

Other applications of caustic soda include the chlorination (sterilisation) of domestic water and waste, and other domestic market products (including for manufacture of hypochlorite) at 145 000 tonnes and the manufacture of sodium cyanide at 90 000 tonnes


Australian demand is 1.2 million tonnes directed to production of alumina and a further 0.25 million tonnes directed to production of domestic market products.


Price of caustic soda has been very volatile ranging from about US$30 per tonne (FOB) to ten-times higher at US$300 per tonne as during the late 1980s. Freight costs to Australia are typically US$40 per tonne resulting in a landed price as low as A$100 per tonne. Market prices are countercyclical to that of its co-product chlorine and chlorine derivatives. 



Australian import is 1.2 million tonnes of caustic soda per year. The caustic soda is imported as 50 per cent liquid.


...more coming soon...


Australian production is less than 0.25 million tonnes.


Australian manufacture is in chloralkali production centres primarily dedicated for the required chlorine which is hazardous and hence expensive to transport so that the caustic soda is a by-product.

Raw Materials

...more coming soon...


A chloralkali plant integrated into a petrochemical complex in Western Australia is being promoted for the Pilbara region given the proximity of gas and salt inputs. A smaller chloralkali plant may also become viable in the Goldfields region of Western Australia with the availability of pipeline gas as discussed in relation to sodium cyanide and ammonium nitrate.