Sodium Lauryl Ether Sulfate

SLES, or Sodium Lauryl Ether Sulfate, has the formula C24H50Na2O5S. It is a yellowish-white paste that acts as a surfactant or anionic detergent. The commercial product is an aqueous solution containing 30–70% SLES by weight. Its properties are similar to those of sodium lauryl sulfate, its non-ether cousin (SLS). Both are widely used in home and industrial cleaners, as well as personal care products.

Manufacturing Process

SLES is produced on the basis of lauryl alcohol (dodecanol), which in turn is obtained from vegetable lauric oils. Laurin oils can be extracted from palm kernel oils or coconut oil. Palm kernel oils account for about 80% of the fatty alcohols and surfactants produced from them, while the remaining 20% are attributed to coconut oil.The manufacturing process is as follows:
- Dodecanol is obtained by hydrogenating the fatty acids and fatty acid esters from palm kernel and coconut oil and then working up the reaction mixture.
- SLES is produced by reacting dodecanol with ethylene oxide. The number of oxyethylene units is usually about 2.
- Sulphur trioxide is then used for sulphation.
- A by-product of this process is 1,4-dioxane, which is harmful to health. The end product with two oxyethylene units, sodium 2-(2-dodecyloxyethoxy)ethyl sulphate, is considered irritating to the skin and eyes.

Shampoos and Personal Care Products

SLES is widely used as a primary surfactant in shampoos, body washes, soaps, and other personal care products. It helps in creating foam, emulsifying oils, and removing dirt and oil from the skin and hair.

Detergents and Cleaning Products

SLES is an effective cleaning agent and is used in household and industrial detergents, laundry powders, dishwashing liquids, and other cleaning products. It helps in breaking down dirt, grease, and stains and facilitates their removal.

Emulsion Polymerization

SLES is used as an emulsifier in the production of synthetic latexes and emulsion polymers. It helps in stabilizing the emulsion and promoting the dispersion of hydrophobic components.

Textile Industry

SLES finds applications in the textile industry as a wetting agent and detergent in textile processing, including dyeing and finishing processes. It helps in improving the wetting properties of fabrics and enhancing the penetration of dyes and chemicals.