Detergents, linear alkylbenzene

Ethylbenzene (Ethylene Alkylation), Cumene and Detergent Linear Alkylbenzene... 

Linear paraffins in the C q to range are used for the production of alcohols and plasticizers and biodegradable detergents of the linear alkylbenzene sulfonate and nonionic types (see Alcohols Plasticizers Surfactants). Here the UOP Molex process is used to extract / -paraffins from a hydrotreated kerosine (6—8). 

Alkylation of benzene using alpha olefins produces linear alkylbenzenes, which are further sulfonated and neutralized to linear alkylbenzene sulfonates (LABS). These compounds constitute, with alcohol ethoxy-sulfates and ethoxylates, the basic active ingredients for household detergents. Production of LABS is discussed in Chapter 10. 

Typical properties of detergent alkylate are shown in Table 10-2. Detergent manufacturers buy linear alkylbenzene, sulfonate it with SO3, and then neutralize it with NaOH to produce linear alkylbenzene sulfonate (LABS), the active ingredient in detergents ... 

Trace aromatics removal from linear paraffins in the Ciq-Cis range is an important step in producing linear alkylbenzene (LAB) which in turn is used to make linear alkylbenzene sulfonate (LAS) an important constituent of detergents. High purity linear paraffins are required to produce superior detergent properties. For this application, MgY and NaX adsorbents are reported to be effective adsorbents in removing aromatics from Cio-C n-paraffins [265-267]. 

The main use of n-paraffins is in the production of linear alkylbenzenes (90%) for the detergent industry. The other uses are solvents and lubricants (7%) and chlorinated paraffins (3%). 

Domestic wastewater contains a large amount of detergents, especially anionic surfactants, such as linear alkylbenzene sulfonates (LAS). A sensitive biosensor containing Trichosporon cutaneum has been developed in Japan and used to monitor river water [128,129]. With this sensor a detection limit of 0.2 mg 1" LAS has been reached. 

The major uses of linear alkylbenzenes are in the manufacture of linear alkyl sulfonates that are used for manufacture of household detergents and industrial cleaners. 

The production of LAB involves the liquid-phase alkylation of benzene with linear monoolefins or alkyl chlorides. Liquid HF is used as catalyst for linear monoolefins. And the A1C13 is used as the catalyst for alkyl chlorides. Nowadays, acidic zeolite catalyst is used for olefin alkylation which generates less waste and reduces manufacture cost. The alkylate is then sulfonated to produce linear alkylbenzene sulfonate for biodegradable detergents. The manufacture of detergents is described in detail in Chapter 27. 

Alkylbenzene. Alkylbenzene is an intermediate for the production of alkylbenzene sulfonate. Alkylbenzene consists of a mixture of phenyl substituted n-alkanes of 9 to 14 carbon atoms. Prior to 1965, alkylbenzene was synthesized from propylene tetramer, obtained by oligomerization of propylene. The resulting hard alkylate was a highly branched chain compound. However, the slow biodegradability of propylene tetramer-based materials soon became apparent and by 1965, most of the detergent industry had switched over to linear alkylbenzene. Extensive research has demonstrated... 

Friedel-Crafts technology and zeolite- or other solid catalyst-based processes are currently used for other aromatic alkylations, in particular for the manufacture of linear alkylbenzenes (LABs) made from C10-C14 olefins (Equation 8), or from the corresponding chloroparaffins and benzene, and also to make m- and p-cymene (isopropyltoluene Equation 9). LABs are used for the production of sulfonate detergents, while cymenes lead to m- and p-cresols through a procedure analogous to that used for the cumene-to-phenol process. 

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