Caustic soda or sodium hydroxide is a widely used alkali.

The chemical formula is NaOH. It is delivered to consumers as 50% water solution. It is specified by technology, economic and ecological issues of production process and transportation.

The paper, pulp and cellulose industries are major users of caustic soda. Other areas where caustic is essential are: the food industry, water treatment, the soaps and detergents sectors, the textile sector, mineral oils. Caustic production is also used in the production of aluminium.