Linear alkylbenzene sulfonate LAS

When comparing secondary alkanesulfonates (SAS) and linear alkylbenzene-sulfonates (LAS), it is obvious that SAS are more readily degraded than LAS. This is somewhat more pronounced at lower temperatures (Table 34). 

Fig. 4.3 Interfacial tension between a solution of C,2/i4-fatty alcohol sulfate (FAS) and linear alkylbenzene sulfonate (LAS) and two different oils as a function of time [43].

Surfactants, such as linear alkylbenzene sulfonates (LAS) and alkylphenol ethoxylates, are present in whitewaters because of their use as cleaning agents or as additives in antifoamers, deinkers, dispersants, etc. The non-ionic surfactants alkylphenol ethoxylates (APEO) degrade to nonylphenol (NP) or to a... 

Larvik furnaces, 21 395—396 LASIII glass, matrix for ceramic—matrix composites, 5 553t LAS acid, 23 554. See also Linear alkylbenzene sulfonate (LAS)... 

The trend of discovering the analytical field of environmental analysis of surfactants by LC-MS is described in detail in Chapters 2.6-2.13 and also reflected by the method collection in Chapter 3.1 (Table 3.1.1), which gives an overview on analytical determinations of surfactants in aqueous matrices. Most methods have focused on high volume surfactants and their metabolites, such as the alkylphenol ethoxylates (APEO, Chapter 2.6), linear alkylbenzene sulfonates (LAS, Chapter 2.10) and alcohol ethoxylates (AE, Chapter 2.9). Surfactants with lower consumption rates such as the cationics (Chapter 2.12) and esterquats (Chapter 2.13) or the fluorinated surfactants perfluoro alkane sulfonates (PFAS) and perfluoro alkane carboxylates (PFAC) used in fire fighting foams (Chapter 2.11) are also covered in this book, but have received less attention. 

Commercial linear alkylbenzene sulfonates (LAS) contain mixtures of several alkyl chain homologues each with a variable number of... 

Based on their use in industrial and domestic applications and abundance in environmental samples, six surfactants were selected by the participants of interlaboratory study I. Two different standard mixture solutions (standards II and 12) were distributed to all participants for the preparation of the calibration graphs. Standard II contained Arkopal N100 (NPEO), Marlamid DF 1218 (coconut fatty acid diethanolamide, CDEA) and Marlon A 350 (linear alkylbenzene sulfonate, LAS) at 1000 mg L-1 for each compound, while standard 12 contained Rewopol NOS 5 (nonylphenol ethoxylate sulfate, NPEO-SO4),... 

Although the marine environment can generally be considered the final destination of industrial and urban wastewater effluents, studies of biodegradation of linear alkylbenzene sulfonates (LAS) in this compartment have been scarce until recently [1—8]. The removal of LAS from the marine medium seems to be an efficient process, as shown by the low levels of LAS detected in samples of both water and sediment [9—11]. High values have only been found in zones close to the direct wastewater effluent discharge points of urban areas [11]. 

A broad range of information pertaining to the toxicity of several classes of surfactants including anionic (linear alkylbenzene sulfonates (LAS), alkylether sulfates (AES), alkyl sulfates (AS), non-ionic (alkylphenol ethoxylates (APEO)), cationic (ditallow dimethyl ammonium chloride (DTDMAC)—a group of quaternary ammonium salts of distearyl ammonium chloride (DSDMAC)) and amphoteric surfactants (alkyl-betaines) is available. Several reviews of the scientific literature have been published [3-5,20]. 

Linear alkylbenzene sulfonate (LAS) and the sodium salt Na-LAS (P550), alkyl sulfate (AS) Ci2-Ci4, alkylether sulfate (AES), alcohol ethoxylate (AE) 1012/60, methylester sulfonate (MES) Ci6-Ci8, Na-lauryl sulfate, 1-octane sulfate Na, 1-decan sulfonate Na, 1-hexadecan sulfonate Na, Laurie alcohol, 1-octanol (A. Caprilico), 1-nonanol, n-decyl-alcohol, 1-undecanol, 1-tridecanol, miristic alcohol (1-tetradecanol), 1-pentadecanol, cetyl-alcohol (1-hexadecanol), 1-hep-tadecanol, estearil alcohol (1-octadecanol), nonadecanol, araquidil alcohol (1-ecosanol), heneicosanol, behenil alcohol (1-docosanol),... 

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]. 

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. 

Jensen, J., Fate and effects of linear alkylbenzene sulfonates (LAS) in the terrestrial environment , Sci. Total Environ., 226, 93-111 (1999). 

Like Soxhlet, sonication is also recognized as an established conventional method, although it is not as widely used. Limited research has focused on sonication per se or its comparison with Soxhlet. Qu et al. [13] developed a method using sonication with methanol for the extraction of linear alkylbenzene sulfonate (LAS) in plant tissues (rice stems and leaves). Both efficiency and accuracy were found to be high. The mean recovery was 89% (84 to 93% for LAS concentration of 1 to 100 mg/kg), and the relative standard deviation (RSD) was 3% for six replicate analyses. Its advantages over Soxhlet extraction were speed (1 hour), less solvent consumption, and smaller sample requirement (2 to 3 g). 

Nonbuilt heavy-duty liquids can contain either a high ratio of nonionic to linear alkylbenzene sulfonate (LAS) or, more recently, a reverse type ratio. Typical formulations of these types of products are given below ... 

FIGURE 3.4 Species sensitivity distributions (SSDs) for pentachlorophenol (PCP) and C12 linear alkylbenzene sulfonate (LAS) using fish estimates from ECOSAR and ICE (Asfaw et al. 2004) using fathead minnow (fhm) as the surrogate species. Note SSDs not including ECOSAR values for fish, daphnids, and algae are noted as -fhm, whereas SSDs including these values are noted as -fhme. Source Asfaw et al. (2004). 

Surfactants such as alkyl sulphates (AS), alkyl ethoxysulphates (AES) and linear alkylbenzene sulfonates (LAS) are the major cleaning ingredients found in household and personal care products. The annual North American consumption volumes of AS and AES for 2003 were estimated to be 260 and 1,083 million pounds, respectively (Modler et al. 2004). 

The anionie surfactants of major importance are the linear alkylbenzene sulfonates (LAS). Other important elasses are alkyl sulfates, sulfonates, and ethoxy-sulfates (AES). Few LC-MS studies have been published. 

Pesticide residues Acetochlor Alachlor Atrazine Carbendazin/Benomyl Cyclodienes, 2,4-D DDE Diuron Glyphosate Metolachlor Organophosphate/Carbamate Pyrethroids Spynosyn Surfactants Alkyl ethoxylate (AE) Alkylphenol ethoxylate (APE) Linear alkylbenzene sulfonate (LAS) Estrogens 17-B-Estradiol (E2) ... 

In the mid-1960s, commercial processes were developed for the production of linear paraffins. These could be used as feedstock to produce linear alkylbenzene sulfonates (LAS), a biodegradable alternative to SDBS. " The majority of synthetic detergent plants built after the 1970s were for the production of LABs rather than DDB. Reformulation with LAS started the phaseout of DDB, and by the end of the 1990s, most DDB plants were no longer in operation or had been converted to production of LAB. 

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