Anionic surfactants alkyl sulfate

Anionic surfactant Alkyl sulfate, alkylbenzene sulfonate, ethoxylated alkyl sulfate, soap 0-10 0-0.3... 

Ion flotation in the presence of surfactants for the treatment of rinses and separation of metal ions is of interest since the sixties [327, 328]. Here, we take only a few examples. The recovery of silver ions from highly diluted solutions is possible by forming a silver-thiourea complex in form of a colloidal precipitate (sublate) followed by sublate flotation with sodium dodecyl benzene sulfonate [329]. Skiylev [330] has developed methods for the removal of non-ferrous metal salts from waste waters. Subject of the investigations were 0.01 - 0.001% solutions of ferrous metal salts. Typical anionic surfactants (alkyl sulfates, alkyl phosphates, alkyl xanthogenates of potassium) or cationic surfactants (quaternary ammonium salts) were used as collectors in ion flotation from diluted solutions. At certain pH, a sublate containing a non-ferrous metal ion was formed, followed by a sublate film formation at the surface due to the rise of the complexes with air bubbles stabilised by the surfactants. 

Anionic surfactants. The main anionic surfactants, alkyl sulfates and alkyl sulfonates as well as ethoxylate derivatives were analysed. C12 and C14 homologues of alkyl sulfates... 

Other Anionic Surfactants Alkyl Ether Sulfates... 

Alkyl and Ether Sulfates. The second largest class of anionic surfactants is sulfated alcohols and ethoxylates. Falling film reactors are also used to sulfate these materials, however, cooling water and sulfation temperature are adjusted to lower values for these materials. The digestion and hydration steps are not required in sulfation and these systems are bypassed. The acids are neutralized immediately to minimize degradation and side reactions in storage. Typical S03 sulfation reactions for alcohols and alcohol ethoxylates are shown in Fig. 36.31. 

Laboratory Treatments. Colorfastness of the dyed wool samples was determined in aqueous and nonaqueous media. Colored samples were cut into 2- X 2-in. squares and sandwiched between multifiber fabrics (Test Fabrics) and undyed wool fabrics of the same dimensions. The fabrics were loosely sewn together by hand with white cotton thread. Two surfactants were chosen for the aqueous treatments Tergitol NPX, a nonionic ethoxylated nonylphenol (Union Carbide) and Orvus WA, an anionic sodium alkyl sulfate (Proctor Gamble). Solutions of 0.1% surfactant in distilled water were prepared. Tests were run in 250-mL Erlenmeyer flasks at a liquor-to-cloth ratio of 50 1. The flasks were placed in an Eberbach constant-temperature shaker bath adjusted to 30 °C and an agitation of 40 cycles/min. Treatment time was 1 h, after which the samples were opened and allowed to dry on blotter paper. This same procedure was used for the nonaqueous treatments. Commercial grade tetrachloroethylene (R. R. Street Co.) with and without 1% Aerosol OT, the anionic surfactant sodium sulfosuccinate (Aldrich Chemical) was selected. The treated samples were removed from the liquids, opened, and dried on blotter paper in a ventilated hood. 

High-performance liquid chromatography is performed using a Hewlett-Packard 1090 chromatograph equipped with a ternary-solvent delivery system, an autoinjector with a 0 -20- u.L injection loop, an oven compartment, and a diode-array UV detector. An ELS detector (Alltech Associates, Deerfield, IL) is connected in series to the UV detector. Hexane, 2-propanol, and water were used for the analysis of nonionic surfactants. Water and tetrahydrofuran (THF) are used for the analysis of anionic surfactants. No preliminary sample preparation is used other than dilution. The nonionic surfactants are diluted 1 40 (v/v) with hexane. The anionic surfactants (alkyl ether sulfates and synthetic and petroleum sulfonates) are diluted 1 20 (v/v) with water-THF (50 50). The calcium sulfonate surfactants were diluted 1 20 (v/v) with a THF-38% hydrochloric acid solution of pH 1. Hydrochloric add is required to prevent salt precipitation by converting any excess water-insoluble caldum carbonate into water-soluble calcium chloride. All diluted samples are... 

The surfactants used in the emulsion polymerization of acryhc monomers are classified as anionic, cationic, or nonionic. Anionic surfactants, such as salts of alkyl sulfates and alkylarene sulfates and phosphates, or nonionic surfactants, such as alkyl or aryl polyoxyethylenes, are most common (87,98—101). Mixed anionic—nonionic surfactant systems are also widely utilized (102—105). 

A.lkyl Sulfosuccinate Half Asters. These detergents are prepared by reaction of maleic anhydride and a primary fatty alcohol, followed by sulfonation with sodium bisulfite. A typical member of this group is disodium lauryl sulfosucciaate [26838-05-1]. Although not known as effective foamers, these surfactants can boost foams and act as stabilizers when used ia combination with other anionic surfactants. In combination with alkyl sulfates, they are said to reduce the irritation effects of the latter (6). 

Three generations of latices as characterized by the type of surfactant used in manufacture have been defined (53). The first generation includes latices made with conventional (/) anionic surfactants like fatty acid soaps, alkyl carboxylates, alkyl sulfates, and alkyl sulfonates (54) (2) nonionic surfactants like poly(ethylene oxide) or poly(vinyl alcohol) used to improve freeze—thaw and shear stabiUty and (J) cationic surfactants like amines, nitriles, and other nitrogen bases, rarely used because of incompatibiUty problems. Portiand cement latex modifiers are one example where cationic surfactants are used. Anionic surfactants yield smaller particles than nonionic surfactants (55). Often a combination of anionic surfactants or anionic and nonionic surfactants are used to provide improved stabiUty. The stabilizing abiUty of anionic fatty acid soaps diminishes at lower pH as the soaps revert to their acids. First-generation latices also suffer from the presence of soap on the polymer particles at the end of the polymerization. Steam and vacuum stripping methods are often used to remove the soap and unreacted monomer from the final product (56). 

As esters of sulfuric acid, the hydrophilic group of alcohol sulfates and alcohol ether sulfates is the sulfate ion, which is linked to the hydrophobic tail through a C-O-S bond. This bond gives the molecule a relative instability as this linkage is prone to hydrolysis in acidic media. This establishes a basic difference from other key anionic surfactants such as alkyl and alkylbenzene-sulfonates, which have a C-S bond, completely stable in all normal conditions of use. The chemical structure of these sulfate molecules partially limits their conditions of use and their application areas but nevertheless they are found undoubtedly in the widest range of application types among anionic surfactants. 

Sodium dodecylbenzenesulfonate is undoubtedly the anionic surfactant used in the greatest amount because it is the basic component in almost all laundry and dishwashing detergents in powder and liquid forms. However, alcohol and alcohol ether sulfates are the more versatile anionic surfactants because their properties vary, with the alkyl chain, with the number of moles of ethylene oxide added to the base alcohol and with the cation. Consequently, alcohol and alcohol ether sulfates are used in almost all scientific, consumer, and industrial applications. 

Ethoxylated methylcarboxylates Propoxyethoxy glyceryl sulfonate Alkylpropoxyethoxy sulfate as surfactant, xanthan, and a copolymer of acrylamide and sodium 2-acrylamido-2-methylpropane sulfonate Carboxymethylated ethoxylated surfactants (CME) Polyethylene oxide (PEG) as a sacrificial adsorbate Polyethylene glycols, propoxylated/ethoxylated alkyl sulfates Mixtures of sulfonates and nonionic alcohols Combination of lignosulfonates and fatty amines Alkyl xylene sulfonates, polyethoxylated alkyl phenols, octaethylene glycol mono n-decyl ether, and tetradecyl trimethyl ammonium chloride Anionic sodium dodecyl sulfate (SDS), cationic tetradecyl trimethyl ammonium chloride (TTAC), nonionic pentadecylethoxylated nonylphenol (NP-15), and nonionic octaethylene glycol N-dodecyl ether Dimethylalkylamine oxides as cosurfactants and viscosifiers (N-Dodecyl)trimethylammonium bromide Petrochemical sulfonate and propane sulfonate of an ethoxylated alcohol or phenol Petrochemical sulfonate and a-olefin sulfonate... 

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. 

A broad range of information pertaining to the toxicity of several classes of surfactants including anionic (linear alkylbenzene sulfonates (LAS), alkylether sulfates (AES), alkyl sulfates (AS), non-ionic (alkylphenol ethoxylates (APEO)), cationic (ditallow dimethyl ammonium chloride (DTDMAC)—a group of quaternary ammonium salts of distearyl ammonium chloride (DSDMAC)) and amphoteric surfactants (alkyl-betaines) is available. Several reviews of the scientific literature have been published [3-5,20]. 

Other widely used anionic surfactants, such as alkyl sulfates and alkylether sulfates (see Chapter 1), have also been thoroughly investigated according to their risk [16]. By means of higher tier... 

---