Alkyl benzene sulfonate , with

For instance, if the surfactant in Fig. 3 (left) scan is an alkyl-benzene sulfonate with a 14 carbon atom alkylate, and it is changed for a 12 carbon atom alkylate, then another scan with the same oil, alcohol, and temperature shows that the optimum salinity becomes S2 = 4.5 wt. % NaCI (Fig. 3 right). It follows that In S has increased by 0.72 unit, hence a should have decreased by 0.72 unit according to... 

Based on petrochemicals, linear alkyl benzene sulfonates (LAS) are the most important surfactants. First description can be found in patents from the mid-1930s [2] using Fischer-Tropsch synthesis and Friedel-Crafts reactions. With the beginning of the 1950s the importance of the class of surfactants rose. The main use is in household and cleaning products. 

Alkyl ether sulfates are/after alkyl benzene sulfonates(LAS),the group of technically important anionic surfactants with the largest production voluJne and product value. They have in comparison with other anionic surfactants special properties which are based on the particular structure of the molecule. These are expressed,for example,in the general adsorption properties at different interfaces, and in the Krafft-Point. Alkyl ether sulfates may be used under conditions, at which the utilization of other surfactant classes is very limited. They possess particularly favorable interfacial and application properties in mixtures with other surfactants. The paper gives a review of all important mechanisms of action and properties of interest for application. 

In most products,alkyl ether sulfates are used in form of mixtures with other surfactants. Alkyl benzene sulfonate (LAS) is the most important anionic surfactant used in combination with alkyl ether sulfates. 

Bartholme t al. (22) found for styrene with persulfate initiation and a sodium alkyl benzene sulfonate emulsifier that there was a discrepancy between their measured value of E (21.7 kJ mol- ) and that calculated (on the assumption that Att = 0) from the expression EN = /5(E - E ). However their value of E (which was derived from measuremlnts of the rate of seeded emulsion polymerization experiments in which N was the same at all temperatures) now seems to be too high probably because the average number of radicals per particle, n < 0.5 at the lower temperatures taking E =32.5 kJ mol-1 as the best estimate, AHg can be calculated rom AHg = /2(E (exp) - E (calc))... 

The results are shown in Figure 27. It can be seen the all the anionics tested show significant effects of the combination with SAE on their sequestering ability. For this effect, the optimum EO mole number for each anionic is different. Since the combination of LAS with STPP gives a calcium ion sequestering ability of only 165 mg/g-detergents by this procedure, the combination of SAE with LAS(Linear Alkyl-benzene Sulfonate), AOS (4-Olefin Sulfonate), SAS(Secondary Alkane Sulfonate) or SDS (Sodium Dodecyl Sulfate) would be recommended for use in heavy-duty detergents. 

Before 1965, the type of surfactant used in this country was alkyl benzene sulfonate (ABS). ABS is very resistant to biodegradation and rivers were known to be covered with foam. Because of this and because of legislation passed in 1965, ABS was replaced with linear alkyl benzene sulfonate (LAS). LAS is biodegradable. 

Alcohol sulfates are not stable in acid and are used in alkaline formulations. C12-C16 alcohol sulfates have excellent detergency, high foam, and good wetting properties. Alcohol sulfates are fully biodegradable under aerobic and anaerobic conditions and compete in performance with petrochemical-derived linear alkyl-benzene sulfonates (LABS). 

Poljrmers. Olefins having 9 to 15 carbon atoms with the unsaturation near the end of the molecule may be used to alkylate benzene to make alkyl benzene sulfonates, as outlined by Griesinger and Nevison (38), Such olefins may be economically prepared by propylene polymerization. 

Effect of Surfactant Concentration. Figure 3 compares results of alkane scans for three concentrations of sodium oleate at constant sodium chloride concentration and pH. The 0.002 M solution is derived from 95% oleic acid, the 0.01 M and the 0.1 M solutions are derived from 99% oleic acid. Both the magnitude and the alkane position of minimum interfacial tension (r = 11) are essentially concentration independent under these conditions. Wade, et al (12) reported a similar invariance in nm with a pure alkyl benzene sulfonate, although there was more change in the minimum value of interfacial tension with the sulfonate concentration than is observed with the carboxylate. The interfacial tension at for 0.01 M sodium oleate is in the range of the values of Table I. Very high interfacial tension (> 10 dynes/cm) was found at 0.0001 M sodium oleate in 0.1 M sodium chloride. 

Commonly used alkyl-aromatic frothers are alkyl-benzene sulfonates (sodium salt) which possess not only frothability but can also be used as collectors especially for sulfide minerals. The effect of an alkyl chain linked with benzene ring on frothing performance is an increase in the frothability with increase in the length of alkyl chains of C5-C12 over which the frothability will usually decrease. 

The increased use of synthetic detergents ( syndets ) can create problems of taste and foaming in the re-use of water. These syndets, measured as alkyl benzene sulfonate (ABS), are not removed by conventional sewage treatments and are not eliminated by water purification processes of coagulation, disinfection, and filtration. Based on an analysis of a number of streams, as of now the concentration of syndets in most streams is below levels that cause difficulties from foam or taste. With the increasing use of syndets, however, the situation could become significant, especially where many communities are located on a single stream with the consequent repeated re-use of the water. 

The method is easy to handle, readily adaptable to online SPE-HPLC systems, and gives good results for naphthalene sulfonates and benzene sulfonates with nitro, chloro, and alkyl groups. However, apart from the fact that a number of hydrophilic benzene sulfonates (e.g.,... 

Synthetic Sulfonates The synthetic sulfonates are reported to be more effective in displacing oil, but are more expensive as compared to petroleum sulfonates. These sulfonates also have better tolerance to metal ions in solution such as Ca" " and Mg" " ". The synthetic sulfonates were introduced in World War II, but these were not available commercially until the late 1940 s. The alkyl benzene sulfonates were the first commercially available important synthetic sulfonate. The aromatic and olefin feedstocks have been identified as the major sources for alkylate preparation. These alkylates are sulfonated with either sulfur trioxide or sulfuric acid to prepare synthetic sulfonates. 

These middle-chain esters are quite similar to those of the fatty acids derived from palm kernel oil and coconut oil. The alkene by-products, with the double bond near the end of the chain, can be transformed into useful linear C12-C14 alcohols by hydroformylation, or transformed into linear alkyl benzene sulfonates. 

Stepan was the first to develop and conunercialize a continuous falling film SO3 sulfonation process. The design is a multitubular unit. The company operates about 12 falling film SO3 sulfonation units in the United States, not only for the production of linear alkyl benzene sulfonates, but substantial amounts of fatty alcohol and fatty alcohol ethoxylates are also sulfated. Other key commercial reactor designs are by Chemithon, Ballestra SpA, Lion, Mazzoni SpA, and Meccaniche Modeme. Several features are common to all falling-film systems. Fatty alcohol and alcohol ethoxylates are reacted at a rate of about 0.3 kg/h/mm with SO3 concentration at about 2-3%. Liquid residence times are estimated at 10-30 s and most units operate with gas velocities in the range of hurricane wind velocities (121-322 km/h). ° Linear alcohols and linear alcohol ethoxylates are by far the easiest to sulfate. Caution is required with branched alcohols as color and conversion can suffer. 

Sodium alkyl benzene- sulfonate (%) Sucrose coconut oil ester (%) Persons with vigorous Reaction Persons with reaction Persons without reaction... 

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