Caustic soda lye 50% solution

In the cosmetics industry, caustic soda is used in the manufacture of hard (sodium) soap, washing detergents, exfoliating mask (peeling and chemical dermabrasion) and aseptics. In the petrochemical industry, the product is used for the refining of crude oil, mineral oils, pitches, asphalt and the extraction of shale gas. In refineries and coking plants, caustic soda is used to modify products from coking coal. In the steel and metallurgical industry, it is used for the production of aluminium from bauxite processing.

Sodium hydroxide is also widely used in the paper-cellulose industry in the process of pulping wood used for the production of paper or regenerated cellulose fibres. Together with sodium sulphate, it is a key component of the white liquor solution used to separate lignin from cellulose fibres in the Kraft process. It also plays an important role in several subsequent stages of bleaching the brown pulp resulting from the pulping process. These steps include oxygen delignification, oxidative extraction and simple extraction, all of which require a strong alkaline environment with pH>10.5 at the end of the steps.

In the construction industry, caustic soda is used in several plasticisers for cement mixes. It helps to homogenise cement mixes, preventing segregation of sand and cement and reducing the amount of water needed for mixing. The lye is also used in the production of water glass. It is an important raw material in the process of producing pigments and dyes for paints - e.g., titanium dioxide.

Sodium hydroxide is an important ingredient in the production of surfactants, washing liquids, and powders, degreasing agents and water softeners. In liquid form it is a component of various detergents. It is used in the textile industry in the production of dyes and rayon. In water treatment processes by increasing the pH, water has a less corrosive effect on the water installation and additionally reduces the content of lead, copper, and other toxic metals that can dissolve in drinking water.

In the pharmaceuticals industry, sodium hydroxide is used for example for the production of aspirin, salicylic acid, or sulfanilamides.

Both sodium hydroxide solid as well as liquid form are widely used in agriculture. Caustic soda is used in livestock breeding for the disinfection of farm premises (stables, cowsheds, poultry houses, sheds, storage rooms), milking equipment and containers for transporting and storing dairy products. It is used in fruit farming to plant disease control (e.g., fungal plant pathogen known as Nectria galligena) and in the protection of grape vines, while in beekeeping for hives cleaning.