Alcohol ethoxy sulfates

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. 

CMCs of some alcohol ethoxy sulfates are given in Table 16. 

Dioxane is an impurity present in alcohol ethoxy sulfates formed during sulfation of the ethoxylated alcohol. 1,4-Dioxane is a carcinogen in rats and mice [312-314] and has been considered as a possible carcinogen to humans [315-317]. However, the no-effect dose in rats is equivalent to a daily intake of dioxane of 9.6-19.0 mg/kg/day, which corresponds to 0.672 g/day for humans. In other studies it has been determined that the threshold for onset of human toxicity of 1,4-dioxane lies above an intake of 76 mg/kg in adult males [318]. Although it seems to be demonstrated that amounts up to 1000 ppm of... 

Matthis, E., M. S. Holt, A. Kiewiet, and G. B. J. Rijs, Environmental monitoring for linear alkylbenzene sulfonate, alcohol ethoxylate, alcohol ethoxy sulfate, alcohol sulfate, and soap , Environ Toxicol. Chem., 18,2634-2644 (1999). 

Surfactants can be divided into four general areas cationic surfactants, anionic surfactants, nonionic surfactants, and amphoteric surfactants. Major anionic surfactants are soaps, linear alcohol sulfates, linear alcohol ethoxy-sulfates, and linear alkylbenzenesulfonates. 

Vashon, R.D., Schwab, B.S. (1982) Mineralization of linear alcohol ethoxylates and linear alcohol ethoxy sulfates at trace concentrations in estuarine water. Environ. Sci. Technol. 16, 433 36. 

A very efficient way to reduce 7k is to incorporate two or three oxyethylene monomers between the amphiphile hydrophobic chain and the polar head group (alcohol ethoxy sulfates). In each case other properties of the amphiphile, such as the surface activity, can be consequently modified. 

FIG. 8.21 Effect of product pH on protease stability in a HDLD containing alcohol ethoxylate and alcohol ethoxy sulfates. (Reproduced from Kravetz, L. and Guin, K.F., J. Am. Oil Chem. Soc., 62, 943, 1985. With permission.)... 

Cal foam NEL-60 Linear primary alcohol ethoxy-sulfate liquid (50% active) Pi lot... 

The pathway of AES biodegradation can be illustrated using a linear primary alcohol ethoxy sulfate as an example. 

Environmental and Human Safety of Major Surfactants. Vol. I. Anionic Surfactants. Part 2. Alcohol Ethoxy Sulfates, a final report to The Soap and Detergent Assoc., New York by Arthur D. Litfie, Inc. Cambridge, MA, 1991, Reference 65913. 

Patty Alcohol Ethoxy Sulfates (Toiletry Grades) (Continued) ... 

Infrared spectroscopy was applied to identify and determine microamounts of the anionic surfactants LAS, branched ABS, alpha olefin sulfonates (AOS), fatty alcohol sulfates (AS), and fatty alcohol ethoxy sulfates (AES) contained in sewage or river waters [112],... 

Anionics are also variably sensitive to water hardness ions this fact may restrict their use in hard water. The lower water solubility and the peculiar interfacial properties of sulfonates Mg salts is sometimes positively exploited to optimize detergent performance. Alcohol ethoxy sulfates are much less sensitive to alkaline-earth ions than alcohol sulfate homologs. 

Applications. Due to their good foaming properties and substantivity on the hair, ester carboxylates are especially suitable in shampoos in combination with alcohol ethoxy sulfates, they reduce skin irritation. 

Description. Alkyl ether sulfates (AES), which are also called alcohol ethoxy sulfates (AEOS), result from the sulfation of an ethoxylated alcohol. As will be mentioned in a later section covering the ethoxylated alcohols, there is usually, and more especially in industrial-grade raw materials, a rather broad distribution in the ethoxylation degree. The ether sulfates are stable under alkaline conditions but are rapidly hydrolyzed under acidic conditions and even under neutral conditions this hydrolysis is ascribed to an autocatalytic acidification process that progressively takes place and continues growing. 

Linear alkylbenzene sulfonate is also used in hand dishwashing, often in combination with AEOS (i.e., alcohol ethoxy sulfate) this surfactant association provides better foam resistance. Due to its very high detersive action, LAS has a low compatibility with skin and is scarcely used in cosmetics, except in antiseborrheic preparations. 

Sulfonated surfactants are also powerful protease deactivators [67]. The presence of the sulfonate group on benzene makes sodium dodecyl benzene sulfonate, also called LAS (linear alkylbenzene sulfonate), more surface active than SDS. As a result, LAS is an even more efficient denaturant than SDS [27] and alcohol ethoxy sulfates [32]. For instance, in a 0.02% LAS solution, the activity of the protease from Bacillus stearothermophilus is reduced to 20% of its value in water [68]. Likewise, the subtilisin saturation by surfactants at pH 7.4 has been reported to occur at surfactant to enzyme ratios (w/w) of 6.3 (SDS) and 3.2 (LAS) [69]. 

For laundry detergents containing mixtures of alkylbenzene sulfonate, alcohol sulfates, or alcohol ethoxy sulfates, sulfonation reactions are either campaigned or produced in two separate units—one for sulfonation, one for sulfation. The respective acids can be blended prior to neutralization to yield a superior product to one made by post-blending of the neutral salts. 

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