Surfactant sulfonate

E. A. Knaggs, CHEMTECH, 436—445 (July 1992), for a review of major surfactant sulfonic acids. 

SFC-FID is widely used for the analysis of (nonvolatile) textile finish components. An application of SFC in fuel product analysis is the determination of lubricating oil additives, which consist of complex mixtures of compounds such as zinc dialkylthiophosphates, organic sulfur compounds (e.g. nonylphenyl sulfides), hindered phenols (e.g. 2,6-di-f-butyl-4-methylphenol), hindered amines (e.g. dioctyldiphenylamines) and surfactants (sulfonic acid salts). Classical TLC, SEC and LC analysis are not satisfactory here because of the complexity of such mixtures of compounds, while their lability precludes GC determination. Both cSFC and pSFC enable analysis of most of these chemical classes [305]. Rather few examples have been reported of thermally unstable compounds analysed by SFC an example of thermally labile polymer additives are fire retardants [360]. pSFC has been used for the separation of a mixture of methylvinylsilicones and peroxides (thermally labile analytes) [361]. 

Naess, O., and Rasmussen, K. E. (1997). Micellar electrokinetic chromatography of charged and neutral drugs in acidic running buffers containing a zwitterionic surfactant, sulfonic acids or sodium dodecyl sulphate — separation of heroin, basic by-products and adulterants. /. Chromatogr. A 760, 245-251. 

The results of one of these comparisons for a typical group II surfactant, sulfonated 4( diethylphenyl )nonane, are shown in figure 4. The plots are of interfacial tension vs. alkane carbon number of EACN of the crude. Another comparison is shown in figure 5, this time for a mixture of two group II surfactants, sulfonated 5(p butylphenyl) decane and sulfonated 4(p butylphenyl) octane. 

A comparison for a group I surfactant, sulfonated 5(p ethylphenyl) dodecane is in figure 6. These three sets of data are typical of the results. Three things may be noted. 

Figure 6. Comparison of alkane and crude oil tensions for a Group I surfactant, sulfonated 5(p-ethylphenyl)dodecane...

Sulfonate groups can also be introduced during the course of the diphosphine synthesis. For example, as shown in Scheme 1, the surfactant sulfonate derivative of bis(diphenylphosphino)pentane is formed by reaction of Li P[C6H4(CH2)3C6H5]2 with (R,R)-2,4-pentanediylditosylate and subsequent sulfonation with sulfuric acid [10]. Here, the phenyl group that is not attached directly to phosphorus is less deactivated for sulfonation. 

Scheme 1 Synthesis of the surfactant sulfonate derivative of 2,4-bis(diphenylphosphino) pentane.

Sodium 1aurylsulfate. Anionic. Sulfonated surfactant Sulfonated surfactant... 

MIRANOL Amphoteric Surfactants - Sulfonated Imidazoline Derivatives ... 

Different mechanisms have been suggested for the adsorption of anionic surfactants on negatively charged surfaces [21]. Multivalent cations in solution such as calcium ions can improve the adsorption of anionic surfactants when the cations adsorb on the surface and do not form insoluble metal soaps with the surfactants. Sulfonate and phosphate group containing surfactants have proven to be particularly suitable [22]. 

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