Linear alkyl benzene

Linear alkylbenzene

Names
Other names LAB, linear alkyl benzene
Identifiers
ECHA InfoCard	100.060.937
Properties
Chemical formula	C6H5CHR1R2 where R1 = CnH2n+1 and R2 = CmH2m+1 m,n are integers m≥0, n≥1 (typically 10-16)
Hazards
Main hazards	flammable, relatively non-toxic
Safety data sheet	MSDS
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y  (what is YN ?)
Infobox references

Linear alkylbenzene (Sometimes also referred as LABs) is a family of organic compounds with the formula C₆H₅C_nH_2n+1. Typically, n lies between 10 and 16, although generally supplied as a tighter cut, such as C₁₂-C₁₅, C₁₂-C₁₃ and C₁₀-C₁₃, for detergent use. The C_nH_2n+1 chain is unbranched. They are mainly produced as intermediate in the production of surfactants, for use in detergent. Since the 1960s, LABs have emerged as the dominant precursor of biodegradable detergents.

Hydrotreated kerosene is a typical feedstock for high purity linear paraffins (n-paraffins), which are subsequently dehydrogenated to linear olefins:

Alternatively, ethylene can be oligomerized (partially polymerized) to produce linear alkenes. The resulting linear mono-olefins react with benzene in the presence of a catalyst to produce the LABs. Hydrogen fluoride (HF) and aluminium chloride (AlCl₃) are the two major catalysts for the alkylation of benzene with linear mono-olefins. The HF-based process is commercially dominant; however, the risk of releasing HF (a poisonous substance) into the environment became a concern particularly after the Clean Air Act Amendment. In 1995, a solid catalyst system (the DETAL process) became available. The process eliminates catalyst neutralization and HF disposal. Consequently, most LAB plants built since then have utilized this process.

Given the large scale applications of LAB-derived detergents, a variety routes have been developed to produce linear alkylbenzenes:

Each process generates LAB products with distinct features. Important product characteristics include the bromine index, sulfonatability, amount of 2-phenyl isomers (2-phenylalkane), the tetralin content, amount of non-alkylbenzene components, and the linearity of the product.

The production of n-paraffins often occurs as part of an integrated LAB plant where the producers start from kerosene as raw material. The UOP process for producing normal paraffin includes a kerosene prefractionation unit, a hydrotreating unit and a Molex unit. The ExxonMobil Chemical technology includes a recovery process and can produce LAB grade n-paraffins from most medium to low sulfur kerosene without the use of a hydrotreater stage upstream. A desulfurization process is needed to reduce the sulfur content of some n-paraffins