Sulfonated alkylnaphthalenes

Sulfonated alkylnaphthalenes Sulfonated- fatty alcohols Sulfur (crude refined)... 

All lnaphthalenesulfonic Acids. The aLkyLnaphthalenesulfonic acids can be made by sulfonation of aLkyLnaphthalenes, eg, with sulfuric acid at 160°C, or by alkylation of naphthalenesulfonic acids with alcohols or olefins. These products, as the acids or their sodium salts, are commercially important as textile auxiUaries, surfactants (qv), wetting agents, dispersants (qv), and emulsifying aids, eg, for dyes (qv), wettable powder pesticides, tars, clays (qv), and hydrotropes. 

In 1994 estimated naphthalene consumption in western Europe and Japan for the production of alkylnaphthalene sulfonates, naphthalene sulfonate formaldehyde condensates, and synthetic tanning agents was... 

AT-Alkyl methanesulfonamides, 23 685 Alkyl monoperoxycarbonic acid, 18 466 Alkylnaphthalenes, 17 84-85 dispersant moieties, 8 706t Alkyl naphthalene sulfonates, 24 146 Alkylnickel, re-complexes of, 17 116 Alkyl nitrites, formation of, 17 165-166 Alkylonium salt hydrates, 14 171... 

Choose alkylnaphthalene sulfonates and sulfosuccinate esters as hydrotropes in formulations where foaming needs to be controlled, as they enhance solubility of anionic surfactants without increasing foam amount [20],... 

Poly (vinyl 2-pyrrolidone) (123) alkylnaphthalene sulfonic acid (97)... 

Sodium Alkylnaphthalene Sulfonate Sodium Alkylaryl Sulfonate Powder (90%)... 

Surfactant solubilization in liquid cleaners may be limited due to a high concentration of the surfactant or a high amount of electrolytes present in the formulations. In order to enhance the solubility and to increase the cloud point for nonionic-based systems, hydrotropes are often added. This phenomenon has already been pointed out in Section 3.5 above, where the cloud points of solutions with nonionic surfactants were elevated upon the addition of alkyl polyglucosides (16). Hydrotropic activity can be evaluated by determining the amount of hydrotrope required to clarify a cloudy solution or the cloud point elevation obtained for a specific concentration of a hydrotrope. The efficacy of hydrotropes varies for different classes of compounds. This has been observed for short-chain alkylbenzene and alkylnaph-thalene sulfonates when added to a number of detergent formulations (21). The alkylnaphthalene sulfonates were found to be more efficient than the alkylbenzene sulfonates in elevating the cloud point. 

Burns, R. L., Hydrotropic properties of some short-chain alkylbenzene and alkylnaphthalene sulfonates, J. Surf. Det., 2, 13-16 (1999). 

Alkyl Aromatics. Related to the alkyl benzenes discussed above are materials based on the so-called polynuclear aromatics such as naphthalene and anthracene. Of this class, the primary surfactant samples prepared and used industrially are the alkylnaphthalene sulfonates. They usually consist of mixtures of mono-, di-, and trialkyl naphthalene sulfonates with the alkyl group usually being in the C2-C4 range. 

Alkylbenzene sulfonates and alkylnaphthalene sulfonates act as hydrotropes to modify solubilities, viscosities, and other properties of surfactants and surfactant formulations. Sodium toluenesulfo-nate (STS) and sodium xylene sulfonate (SXS) are the best-known hydrotropes, however, alkylnaphthalene snlfonates also possess hydrotropic properties. Hydrotropicity is the amount of different hydrotropes required to achieve clear solutions. The amount of different hydrotropes, for example, SXS, STS, sodium cumene sulfonate (SCS), and others, in light-duty liquid (LDL) detergent formulations is given in Figure 14.1. There seems to be no trend different hydrotropes are (more or less) similarly efficient in different formulations. 

The toluene, xylene, cumene, and alkylnaphthalene sulfonates, specifically considered in this chapter, are generally prepared by sulfonation of the corresponding aromatic hydrocarbon followed by neutralization with the appropriate base. Gilbert s monograph on sulfonation reactions [1] forms the primary basis for the discussion on their synthesis, that is, the sulfonation of the aromatic portion of the starting raw materials—alkylbenzenes and alkyl naphthalenes. 

GAF CHEMICALS CORP. NBKAL Sodium Alkylnaphthalene Sulfonates ... 

Type sodium alkylnaphthalene sulfonate Form powder % Active 70... 

A range of the salts of alkylbenzene sulfonates and alkylnaphthalene sulfonates, which give improved electrolyte stability and are not subject to hydrolysis in acid media as are the sulfated alcohols. Sodium dodecylbenzene sulfonate is widely used. 

Alkylnaphthalene sulfonates, though a distinct class, have many of the properties of petroleum sulfonates and are analyzed by the same general procedures. Their application is mainly in textiles. 

Because their solubility properties differ from those of other anionic surfactants, petroleum sulfonates are analyzed by specialized methods. ASTM standard D3712 applies to characterization of petroleum sulfonates (110). Alkylnaphthalene sulfonates are generally characterized according to the same procedures given below for petroleum sulfonates. 

ISO standard 1104 applies to the specification analysis of alkylnaphthalene sulfonates (8). This and most other standard methods referenced in this section specify assay by gravimetric analysis after removal of unsulfonated material and correction for other impurities. 

Information provided by UV sjrectroscopy is usually limited to showing the presence or absence of an aryl group in the structure, although an experienced spectroscopist can often also distinguish phenyl from naphthyl character. Once other tests have indicated that an unknown surfactant is anionic, the UV spectram will indicate if it is an alkylbenzene-sulfonate or alkylnaphthalene sulfonate. If the surfactant is cationic, the UV spectrum will indicate whether or not one of the substituents is benzyl or pyridyl. If the surfactant is nonionic, the UV absorbance spectram indicates if a phenol or a naphthol group is present. With experience, it is possible to identify certain other functionalities of pure surfactant compounds (26). 

Isolation of alkylnaphthalene sulfonates from pesticide formulations... 

Alkylnaphthalene sulfonates determination in formulations separa- Merck LiChrosorb 10 RP-8,4.6 x 250 mm, 40-C Gradient, MeOH/H20, pH adjusted to 2.75 with H3PO4 UV, 290 nm 61... 

If equipment is available to scan the UV reflectance spectra of the spots, LAS and the aromatic hydrotropes show typical absorption at about 225 and 265 nm. The for alkylnaphthalene sulfonates is somewhat higher. The aromatic compounds can also be detected without a visualizing agent, since they will quench the fluorescence of TLC plates pretreated with a fluorescing agent, appearing as dark spots under UV light. 

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