Linear alkyl benzenes

Industrial chemicals, including those used for the manufacture of detergents such as linear alkyl benzene (LAB) and of coatings, dyestuffs, agrochemicals, pharmaceuticals, and explosives. 

The production of linear alkyl benzenes (LABs) is carried out on a large scale for the production of surfactants. The reaction involves the reaction between benzene and a long-chain alkene such as dodec-l-ene and often gives a mixture of isomers. Greco et al. have used a chloroaluminate(III) ionic liquid as a catalyst in the preparation of LABs [83] (Scheme 5.1-53). 

Linear alkyl benzene sulfonates (LAS). Straight-chain anionic surfactants. Somewhat slow to biodegrade. Most common surfactants in use. 

Based on petrochemicals, linear alkyl benzene sulfonates (LAS) are the most important surfactants. First description can be found in patents from the mid-1930s [2] using Fischer-Tropsch synthesis and Friedel-Crafts reactions. With the beginning of the 1950s the importance of the class of surfactants rose. The main use is in household and cleaning products. 

Linear Alkyl Benzene from linear olefins with A1C13 catalyst, brochure, Enichem Augusta Industrial, Via Medici del Vascello 26, 20138 Milan, Italy. 

Figure 4.6. General scheme for the synthesis of linear alkyl benzenes, precursors to surfactants. Control over pore size of the catalyst can suppress the second alkylation almost completely. Given the ease with which the pore size can be chosen, one can design an effective catalyst for any particular reaction, and allow the selective and clean production of the desired mono-alkyl product, thus eliminating much of the waste associated with the process.

Hon-Nami and Hanya [187,188] used chloroform extraction to extract linear alkyl benzene sulfates from seawater prior to analysis by GC-MS. 

Detal [Detergent alkylation] A process for making detergent alkylate, i.e., alkyl aromatic hydrocarbons such as linear alkyl benzenes, as intermediates for the manufacture of detergents, by reacting C10-C13 olefins with benzene in a fixed bed of an acid catalyst. Developed by UOP and CEPSA as a replacement for their Detergent Alkylate process, which uses liquid hydrogen fluoride as the catalyst. Demonstrated in a pilot plant in 1991 and first commercialized in Canada in 1996. Offered by UOP. 

Trehy et al. [5] determined linear alkyl benzene sulphonates in sediments in amounts down to 0.5mg kg-1 using this technique. 

This technique has been used to determine linear alkyl benzene sulphonates in sludges [9, 11]. 

Holt and Bernstein [3] conducted a second monitoring exercise to determine LAS along with linear alkyl benzene in sludge-amended soils. Analyses of the anionic surfactant followed the previously established method [2], The agricultural lands sampled had all been surface spread with primary or anaerobically digested sludge. In seven out of nine soil samples collected from fields with sludge application in previous years, the mean LAS level was below... 

Neutral oil products,< -j N-paraffin Spray oils, Transformer oils, Turbine oils, Machine oils, Benzene, Cumene, Gas oils, Linear alkyl benzene. 

A wide range of anionic surfactants (Fig. 23) has been classified into groups, including alkyl benzene sulfonates (ABS), linear alkyl benzene sulfonates (LAS), alcohol sulfates (AS), alcohol ether sulfates (AES), alkyl phenol ether sulfates (APES), fatty acid amide ether sulfates (FAES), alpha-olefin sulfates (AOS), paraffin sulfonates, alpha sulfonated fatty acids and esters, sulfonated fatty acids and esters, mono- and di-ester sulfosuccinates, sulfosuccinamates, petroleum sulfonates, phosphate esters, and ligno-sulfonates. Of the anionic surfactants, ABS and LAS continue to be the major products of anionic surfactants [314, 324]. Anionic surfactants have been extensively monitored and characterized in various environmental matrices [34,35,45,325-329]. 

The large demand for benzene is due to its use as a starting material in the production of polystyrene, acrylonitrile styrene butadiene rubber, nylons, polycarbonates and linear alkyl benzene detergent. All of these final chemical products that are suitable to form into consumer goods have multiple chemical transformations in various industrial processes to obtain them from benzene. Because the production of benzene does not involve a liquid adsorptive process on a zeolite, these processes are not described here but can be found in other sources. However, it is important to note that benzene is typically a large byproduct from an aromatics... 

C10-C14 long paraffin dehydrogenation is a key-step for linear alkyl benzene (LAB) production. However, this reaction, which requires monofunctional catalysis, is implemented on Pt-Sn catalysts deposited on controlled acidity alumina. It is generally associated with several secondary reactions, among which aromatic formation is extremely problematic it is catalyzed by a metallic phase (M) or by residual support (A) activity. Indeed, on the one hand, these arylaromatics are very good coke precursors and are consequently responsible for a large part of the... 

Feijtel, T.C.J. and Belanger, S.E. (1999) Predicted no-effect concentrations and risk characterization of four surfactants linear alkyl benzene sulfonate, alcohol ethoxylates, alcohol ethoxylated sulfates, and soap. Environ Toxicol Chem, 18, 2653-2663. 

Cal soft F-90 Sodium linear alkyl benzene sulfonate 90% Pi lot... 

Linear alkyl benzene sulfonate (LAS) CHi(CHj),OS03Na (Jr ranges from 9 to 17) Alkyl sulfate... 

Roberts, D.W. 1989. Aquatic toxicity of linear alkyl benzene sulfonates (LAS)—A QSAR analysis. Communicaciones presentadas a las Jornadas Espanol de la Detergencia 29, 35-43. 

Lunar, L., S. Rubio, and D. Perez-Bendito. 2004. Differentiation and quantification of linear alkyl benzene-sulfonate isomers by liquid chromatography-ion-trap mass spectrometry./. Chromatogr. A 1031 17-25. 

Industrial effluents Organic compounds chloro- and nitrophenols, nonionic surfactants, linear alkylated benzene sulfonates, benzene and naphthalene sulfonates, estradiol, ethinyl estradiol V. fischeri (ToxAlert 10, ToxAlert 100) There were certain correlations between the results of the chemical analyses and bioassays to a large extent, however, the composition of the samples remained unknown Distinct correlations were found between the inhibition of bioluminescence and compound content, but only in the case of nonylphenol, nonylphenol carboxylate, nonylphenol ethoxylate, and chlorophenols 84... 

In one process (Fig. 1), linear paraffins are dehydrogenated to linear olefins that are then reacted with benzene over a solid heterogeneous catalyst to produce the linear alkyl benzenes. Usually, the paraffins are of the C10 to C14 chain length. 

The results are shown in Figure 27. It can be seen the all the anionics tested show significant effects of the combination with SAE on their sequestering ability. For this effect, the optimum EO mole number for each anionic is different. Since the combination of LAS with STPP gives a calcium ion sequestering ability of only 165 mg/g-detergents by this procedure, the combination of SAE with LAS(Linear Alkyl-benzene Sulfonate), AOS (4-Olefin Sulfonate), SAS(Secondary Alkane Sulfonate) or SDS (Sodium Dodecyl Sulfate) would be recommended for use in heavy-duty detergents. 

Linear alkyl benzene sulphonates Li Chrosorb 0.05M NaC104, acetonitrile (2 3) Fluorometric excite, 225nm emission 275nm lOng O.lmg IP1 [84]... 

Other organic compounds that have been determined in sewage effluents include the following (see Table 15.13) hydrocarbons, alcohols, carboxylic acids, esters, chlorobenzenes, nitrosamines, ethylene diamine tetraacetic acid, nitriloacetic acid, organophosphorus compounds, linear alkyl benzene sulphonates, methyl mercaptan, polychlorobiphenyls and chlorinated insecticides. 

Belanger SE, Bowling JW, Lee DM, LeBlanc EM, Kerr KM, McAvoy DC, Christman SC, Davidson DH. 2002. Integration of aquatic fate and ecological responses to linear alkyl benzene sulfonate (LAS) in model stream ecosystems. Ecotoxicol Environ Safety 52 150-171. 

Another material on the horizon is MLABS (modified LABS), a branched chain development for lower wash temperatures. Procter Gamble patented this material in the late 1990s but it has not found commercial support due to the low margins in the industry and the need for substantial investment to modify the feedstock. Interest in MLABS remains as the modifications have overcome most of the performance deficiencies of linear alkyl benzene sulphonate (LABS). 

---