Linear alkyl benzene sulfonic acid (LABSA or LAS)

LABSA or Linear alkyl benzene sulfonic acid with C18H30O3S as its chemical formula is synthesized industrially by sulfonating linear alkyl benzene. LAS or Linear alkyl benzene sulfonate, the world’s most applicable synthetic surfactant, which contains the innumerous salts of sulfonated alkylbenzenes, is mostly used in detergents and many other industrial applications. The LABSA market is related to LAS production. And because of its biodegradability, it replaced with nonlinear alkylbenzenes.

Linear alkyl benzene sulfonic acid is the most common synthetic surfactant due to its approx. Affordable cost, high operational properties, and because of its structure. this product is grouped as biodegradable chemicals and as a result, it is counted as one of the most useable chemical products in detergents. LAS can be applied in both acidic and alkaline processes and also in liquid and powder appearances. It also matches able with other surfactants. It may be applied with some non-ionic and cationic surfactants to ameliorate the cleaning capability of detergents.


Chemical and Physical properties of LABSA

Property Value
Appearance Brown liquid
Boiling Point 315 °C
Density 1.06 g/ml
Molar Mass 326.49 g/mol
Molecular Formula C18H30O3S
Synonyms LABSA

Lauryl benzene sulfonic Acid

Lauryl benzene sulfonate

Linear Alkyl benzene Sulphonic Acid


Dodecyl Benzene Sulphonic Acid

Dodecyl Benzene Sulfonic Acid

Chemical structure


Linear alkyl benzene sulfonic acid applications

Linear alkyl benzene sulfonic acid mainly use is for manufacturing household detergents containing washing powders and liquids, dishwashing liquids and many other detergents. More than 80% of LAS produced worldwide is used in detergent production. In addition to its usages in detergents it has many other applications that are listed below:

1) coupling agent

2) emulsifier in herbicides and other chemicals.

3) textile industry

4) wetting or dispersing agent.


Synthesis of LABSA

They are nonhazardous materials synthesized by the sulfonating process. The structure of LAS and as a result, its application differs in physical and chemical properties due to the alkyl chain length. The linear alkyl benzene is primarily material is synthesized by the alkylation of benzene with n-paraffin in attendance of catalysts like hydrogen fluoride (HF) or aluminum chloride (AlCl3).  The general method to produce Linear Alkyl benzene Sulfonic acid (LAS) is the sulfonating of Linear Alkyl benzene (LAB) with sulfur trioxide (SO3).

Industrially production of this material is due to multitude falling film reactors. In this kind of reactors, a diluted gaseous stream of SO3 in dry air is contacted with liquid LAB. after batch process LAS is thwarted to the required salt. In general, Surfactants are utilized in the industry required to enhanced contact between polar and non-polar mediums such as oil and water.

LABSA structure



Hazardous effects on the environment

Linear alkyl benzene sulfonate and Linear alkyl benzene sulfonic acid have no detrimental result on agricultural crops. The research’s on biodegradability of this product has been studied in natural media. Studies have presented that linear alkyl benzene sulfonate does not have risky effects on the environment. Linear alkyl benzene sulfonate has a half-life of about one day in wastewater sludge and natural water resources and a half-life of one to three weeks in soils media. Aquatic environmental safety evaluations have also presented that the material has not hazardously effect in these media.



  • Tully, P. S. (2000). Sulfonic acids. Kirk‐Othmer Encyclopedia of Chemical Technology
  • Basry Attar, M. (2010). Production of Linear Alkybenzene Sulfonic Acid (LAS) at High Pressure in Supercritical Carbon Dioxide Medium (Master’s thesis, University of Waterloo)


Leave a Reply

Your email address will not be published. Required fields are marked *