Anionic surfactants sulfo fatty acid ester

Also the a-ester sulfonates are less important today. In the Federal Republic of Germany, for example, the total production of surfactants was about 700,000 t/a in 1993. For a more detailed analysis of different types of surfactants, use must be made of data collected before the unification of Germany. In 1988 the consumption of surfactants in detergents was about 227,500 t/a, the consumption of anionic surfactants was about 116,000 t/a and less than 1000 t/a of a-sulfo fatty acid esters [5] (the values refer to German Detergent Law). 

The analytical methods for a-sulfo fatty acid esters reported in the literature deal with the determination of the surfactants in different matrices like detergents or product mixtures from the fabrication. The methyl esters of a-sulfo fatty acids can be separated from a mixture of different surfactants together with sulfonated surfactants by adsorption on an anionic exchanger resin such as Dowex 1X2 or 1X8. Desorption from the exchanger resin is successful with sodium hydroxide (2%) in a 1 1 mixture of isopropanol and water [105]. 

Gravimetric and volumetric methods are practicable for the quantitative determination of the a-sulfo fatty acid esters. Using gravimetric methods the surfactant is precipitated with p-toluidine or barium chloride [105]. The volumetric determination method is two-phase titration. In this technique different titrants and indicators are used. For the analysis of a-sulfo fatty acid esters the quaternary ammonium surfactant hyamine 1622 (p,f-octylphenoxyethyldimethyl-ammonium chloride) is used as the titrant [106]. The indicator depends on the pH value of the titration solution. Titration with a phenol red indicator is carried out at a pH of 9, methylene blue is used in acid medium [106], and a mixed indicator of a cationic (dimidium bromide) and an anionic (disulfine blue VN150) dye can be used in an acid and basic medium [105]. 

The tt-sulfo fatty acid esters represent another class of anionic surfactants. Methyl ester sulfonates (MES) are surfactants that are derived from a variety of methyl ester feedstocks such as coconut, palm kernel, palm stearin, beef tallow, and soy. Palmitic and stearic acid derivatives lead to good detergency because of the long hydrophobic residues [3, 4]. The sensitivity of MES to water hardness is similar to AOS and small compared to LAS and SAS. MES have exceptional dispersion power with respect to lime soap. They have only been used in a few Japanese detergents [3, 4]. 

In general and with respect to RR, - surfactants are the most interesting ingredients of d. because aside of LAS (linear alkylbenzene sulfonate), almost all major surfactants are derived from - fats and oils. Anionic and nonionic surfactants are used in heavy-duty d. for soil removal, pigment dispersion, desirable foaming, wetting, and solubilization of all kinds of stains. From the RR-derived products, mainly - fatty alcohol sulfates and fatty alcohol ether sulfates are, and - a-sulfo fatty acid methyl esters may be, used. - Fatty alcohol ethox-ylates are added as nonionic surfactants and impart detergency at lower temperatures and for synthetic... 

Anionic This group has been classified into subgroups, including alkyl benzene sulfonates, hnear aUcyl benzene sulfonates, alcohol sulfates, alcohol ether sulfates, alkyl phenol ether sulfates, fatty acid amide ether sulfates, alpha-olefin sulfates, paraffin sulfonates, alpha sulfonated fatty acids and esters, sulfonated fatty acids and esters, mono- and di-ester sulfosuccinates, sulfo-succinamates, petroleum sulfonates, phosphate esters, and ligno-sulfonates. Anionic surfactants have been extensively monitored and characterized in various environmental matrices [140-148]. 

SMEs and sulfonated fatty acids are commercially available as blends for use in household and personal cleaning products. As cleaning and personal-care formulations become more concentrated and milder, alpha-sulfo fatty derivatives will become even more attractive. Also since methyl esters are an abundant feedstock, their conversion to SMEs for use as bulk anionics is likely to grow. As quoted by Ed A. Knaggs, a former Stepan employee As already stated, alpha sulfo fatty derivatives have exceptional and unique properties which can be varied and tailored to meet an extremely wide variety of surfactant applications Hence, their acceptance is basically limited only by research,... 

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