Anionic surfactants alkyl aryl sulfonate

Emulsifiers. Removing the remover is just as important as removing the finish. For water rinse removers, a detergent that is compatible with the remover formula must be selected. Many organic solvents used in removers are not water soluble, so emulsifiers are often added (see Emulsions). Anionic types such as alkyl aryl sulfonates or tolyl fatty acid salts are used. In other appHcations, nonionic surfactants are preferred and hydrophilic—lipophilic balance is an important consideration. 

Ammonium salts of alkenyl succinic half-amides have teen described for use as corrosion inhibitors in oil and gas production technology to combat corrosion by media containing CO2, H2S, and elemental sulfur [1366]. The inhibitor composition may contain a dispersing agent, such as a low molecular weight or polymeric anionic surfactant like an alkylsulfonic acid or an alkyl-aryl sulfonic acid. 

Detergent In relationship to fuel technology, a detergent is an oil-soluble surfactant added to fuel aiding in the prevention and removal of deposits. Examples include anionic alkyl aryl sulfonates, cationic fatty acid amides, or nonionic polyol condensates. 

For anionic surfactants colorimetric methods utilize the formation of an ion pair between the surfactant anion and a cationic dye. Similarly to two-phase titration, colorimetric determination is based on the fact that the ion pair is extractable into organic solvent, while the dye by itself is not. A characteristic example of the analysis of anionic surfactant is the determination of alkylsulfates and alkyl(aryl)sulfonates as their complex with methylene blue extracted into chloroform [31]. The absorbance of chloroform extract is measured at 625 nm versus chloroform background. This methods allows one to analyze alkylsulfates and alkyl(aryl)sulfonates separately. Alkylsulfates, in contrast to sulfonates, are easily hydrolyzed by hydrochloric acid. The products of hydrolysis do not interact with methylene blue and are not transferred into chloroform. Some other cationic dyes, such as dimidium bromide, can also be used. In fact, the use of the latter allows one to achieve much higher sensitivity than that obtained with methylene blue. 

Most commonly, in the emulsion polymerization of vinyl acetate, anionic surfactants are used either alone or in combination with a protective colloid. Typical examples of surfactants which have found application are Aerosol OT (sodium dioctylsulfosuccinate), alkyl aryl sulfonate salts (e.g., Santomerse-3), sodium lauiyl sulfate, etc. A study of the kinetics of the vinyl acetate polymerization in the presence of sodium lauryl sulfate indicated that the rate of polymerization was proportional to the square root of the initiator concentration and the 0.25th power of the number of particles. The number of particles were proportional to the 0.5th 0.05 power of the surfactant concentration but independent of the level of potassium persulfate. The intrinsic viscosity of the final polymer was said to be independent of the initiator concentration and of the munber of polymer particles. These observations were said to suggest that the mechanism of the vinyl acetate polymerization in emulsion resembles that of vinyl chloride [153]. 

The formulation scan and dual compensating scan techniques were carried out on an experimental basis first with anionic surfactant s) tems such as alkyl aryl sulfonates, which were the primary candidates for enhanced oil recovery because of their low price and availability. 

K is found to be 0.16 0.01 for alkyl aryl sulfonate sodium salts and 0.10 0.02 for alkyl sulfates and fatty acid sodium salts. The temperature coefficient ar is approximately 0.01 for all anionic surfactants however, this value may be inaccurate ( 20%), and a change in temperature over the whole O-IOO C range does not considerably affect the formulation [32]. 

TTig anionic surfactants commonly employed are mainly sulfonates, particularly alkyl aryl sulfonates [106,107,108,109,110,111]. It is primarily due to their hydrophobic nature that the anionic surfactants act as anticaking agents i.e., this increases the contact angle of the fertilizer solution and reduces the ten e strength erf the caking bond. 

Anionic surfactants are typically sodium salts of alkyl sulfates, alkyl sulfonates, alkyl aryl sulfonates and sulfosuccinates. The alkyl and/or aryl group is ideally selected for optimum affinity to the particulate surfaces. Anionic siufactants are often employed to serve simultaneously as dispersants, although it is not uneommon for a paint to contain both surfactants and dispersants for optimum effect. 

The procedure is suitable for determination of anionic surfactants in concentrates and in detergent formulations and is used for assay of alkyl aryl sulfonates, alkyl sulfates, sulfated APE and AE, and sulfosuccinates. As described in Chapter 1, alkane monosulfonates require special precautions. Phosphate surfactants will generally not be determined. Since the analysis is conducted at pH 2, soap is not determined. Hydrotropes in low concentrations do not interfere, nor do most other detergent constituents. 

The surfactants (qv) used in the emulsion polymerization of acryUc or methacrylic monomers are classified as anionic, cationic, or nonionic. Anionic surfactants, such as alkyl sulfates and alkylarene sulfonates and phosphates, or nonionic surfactants, such as alkyl or aryl polyoxyethylenes, are most common. Mixed anionic nonionic surfactant systems are also widely utilized. 

At the end of the 1990s statistics show that the non-ionic surfactants achieved the highest growth in production rates world-wide, though anionic surfactants (anionics) maintained the dominant position in the surfactant market. Today they are produced in a larger variety by the petrochemical industry than all other types of surfactants. Their production spectrum covers alkyl sulfates (ASs), secondary alkane sulfonates (SASs) and aryl sulfonates and carboxylates via derivatives of partly fluorinated or perfluorinated alkyl surfactants to compounds with an alkylpolyglycolether substructure combined with an anionic moiety such as alkylether sulfates (AESs), phosphates, phosphonates or carboxylates. 

In dyeing, surfactants are used as wetting agents. They are also used in the formulation of disperse dyes. A stable suspension of the dye is prepared with the help of an anionic surfactant, such as alkyl or aryl alkyl sulfonate. It has been shown that dyeing takes place through the aqueous phase by the slow dissolution of the solid dye particles (61, 62). The presence of the surfactant helps the dissolution of the dye. 

The types of surfactants used in an emulsion polymerization span the entire range of anionic, cationic, and nonionic species. The most commonly used soaps are alkyl sulfates such as sodium lauryl sulfate [151-21-3], alkylaryl sulfates such as sodium dodecyl benzene sulfonate [25155-30-0], and alkyl or aryl polyoxyethylene nonionic surfactants (87,101-104). Product stability and particle size control are the driving forces which determine the types of surfactants employed mixtures of nonionic and anionic surfactants are commonly used to achieve these goals (105-108). 

Most organic corrosion inhibitors used in cleaning solutions will not prevent ferric ion corrosion. Special chemicals were developed to reduce this problem. Alfandry demonstrated that hexamethylenetetramine will protect steel in HCI, but the protection is reduced by the presence of Fe + ions. However, the protection provided to steel in sulfuric acid is improved by the addition of ferric ions to a solution inhibited by phenylthiourea. Streicher reported that ferric ion corrosion of steel in sulfuric acid can be reduced by a mixture of diorthotolylthiourea and an anionic surfactant, such as an alkyl-aryl sodium sulfonate. Sulfonium salts also were used as ferric ion inhibitors. These inhibitors are effective in a variety of mineral and organic acids, but they are most effective in acidic (pH of 5) EDTA solutions. The sulfonium salts were shown to electroreduce at the corrosion potential to form a hydrophobic product (hydrocarbon) that may enhance the protection of the steel from oxidation by the ferric ion. 

Snrfactants are employed to stabihze the emulsion polymer particles anionic, cationic, and steric stabihzers are all used for the production of latexes, depending on whether one wants a negative, positive, or neutral potential surface on the formed pol5uner particle. The specific anionic options available for use are alkyl sulfates, alkyl sulfosuccinates, and alkylarene sulfonates and phosphates. Standard nonionic surfactants include alkyl or aryl polyoxyethylenes. In recent years, alkyl phenol ethoxylates have fallen into disfavor because of their reported problems with bioaccumulation in aquatic hfe. This still somewhat controversial, environmentally-driven issue has necessitated the use of alternative surfactants which have a lower impact on the environment. Typically, the aryl ring is eliminated to solve this problem. 

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