What is caustic soda used for?
Caustic soda - or sodium hydroxide - is the natural co-product of chlorine production; indeed, the laws of chemistry define that for every tonne of chlorine you produce, about 1100 kg of caustic soda is also produced, together with 28 kg of hydrogen.
The caustic soda is widely used in industrial processes.
It constitutes an essential reactant in the production
of many useful organic chemicals (more than 30 % of
caustic production goes into this application).
Inorganic chemicals like paints, glass and
ceramics and uses in fuel cell production
and cosmetics are also very important.
The paper, pulp and cellulose industries are
major users of caustic soda.
Other areas where caustic is essential are: the food
industry, water treatment (for the flocculation of heavy
metals and acidity control), the soaps and
detergents sectors, the textile
sector (as a bleaching agent), mineral oils (preparation of greases
and fuel additives) and the synthesis of the synthetic
About four per cent of caustic production is used in the process
of refining aluminium from its ore bauxite.
The remainder of the caustic production (more than 17%) has
miscellaneous applications, like the synthesis of pharmaceutical
compounds, rubber recycling and the neutralisation of acids.
Last update: 10/2013