Sodium fatty alcohol sulphates, sodium dodecyl sulfate (SDS or NaDS), or sodium lauryl sulfate (SLS) is an organic compound with the formula CH3(CH2)11OSO3Na. It is an anionic surfactant used in many cleaning and hygiene products. The salt is of an organosulfate consisting of a 12-carbon tail attached to a sulfate group, giving the material the amphiphilic properties required of a detergent. Being derived from inexpensive coconut and palm oils, it is a common component of many domestic cleaning products.
SLS is synthesized by treating lauryl alcohol with sulfur trioxide gas, oleum, or chlorosulfuric acid to produce hydrogen lauryl sulfate. The industrially practiced method typically uses sulfur trioxide gas. The resulting product is then neutralized through the addition of sodium hydroxide or sodium carbonate. Lauryl alcohol is in turn usually derived from either coconut or palm kernel oil by hydrolysis, which liberates their fatty acids, followed by hydrogenation.
Due to this synthesis method, commercial samples of SLS are often a mixture of other alkyl sulfates, dodecyl sulfate being the main component. SLS is available commercially in powder and pellet forms. It seems the pellet form dissolves faster than the powder form in water.
SLS is mainly used in detergents for laundry with many cleaning applications. SLS is a highly effective surfactant and is used in any task requiring the removal of oily stains and residues. For example, it is found in higher concentrations with industrial products including engine degreasers, floor cleaners, and car wash soaps. It is found in toothpastes, shampoos, shaving foams, and bubble bath formulations in part for its thickening effect and its ability to create a lather.
Some species of insects are attracted to sodium lauryl sulfate or anionic surfactant, even in small amounts, and are then killed by it. It is the main active ingredient in many house fly killers. Sodium lauryl sulfate is commonly used in preparing proteins for electrophoresis. It is used in the analysis of hemoglobin.