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Dodecylbenzene sulphonate

Surfactants. These enhance the colloid stability against mechanical and chemical stresses, help to disperse fillers, aid in wetting and enhance foaming. The most common surfactants are dodecylbenzene sulphonates and potassium oleate. [Pg.655]

An example of a highly exothermic reaction carried out in this manner is provided by the manufacture of dodecylbenzene sulphonic acid. The reactor is charged with dodecylbenzene and 20% oleum is fed in continuously at a rate which is regulated to give a uniform temperature during the sulphonation reaction. The conversion is thus effectively controlled by the rate of oleum addition rather than the rate of the chemical reaction. [Pg.59]

Fig. 7.1 shows the trace obtained from the analysis of undegraded linear alkylbenzene sulphonate (LAS) mixture (sodium dodecylbenzene sulphonate). Peak identifications were made by co-injection with pure undegraded linear alkylbenzene sulphonate compounds and confirmed by analysis of the undegraded linear alkylbenzene sulphonate mixture by desulphonation followed by gas chromatography of the resultant alkylbenzenes on a 15m OV-1 support coated open-tubular column. [Pg.192]

An example of the separation of the anilides of the eight lowest straight-chain carboxylic acids on sodium dodecylbenzene sulphonate is shown in Fig. 5.14. The problem of the procedure described above consists in that formanilide cannot be prepared as CO, SO2 and HC1 are produced by the action of thionyl chloride on formic acid. Formanilide must, therefore, be prepared in an aqueous medium, the other acids must be extracted into a non-aqueous medium. The yield of the extraction varies considerably depending on the type of the acid, and the presence of water in the reaction medium may affect the reaction yield significantly, which makes quantitative analysis difficult. Condensates with toluidine, which were used for the determination of formic acid by GC, are prepared by an analogous procedure. As other toluidine isomers may serve as the reagents, formyl derivatives have been suggested for the separation of these substances [181]. [Pg.123]

Fig. 5.14. Separation of anilide derivatives of Cj -Cs straight-chain carboxylic acids. Peaks 1 = propionic 2 = n-butyric 3 = acetic 4 = n-valeric 5 = n-hexanoic 6 = formic and n-heptanoic 7 = n-octanoic acid STD = methyl myristate. Conditions glass column, 12 ft. x 3 mm I.D., 2.5% (w/w) sodium dodecylbenzene sulphonate on Chromosorb G (60-80 mesh, NAW) nitrogen inlet pressure, 15 p.s.i. temperature, 200°C. (Reproduced from/. Chromatogr., 51 (1970) 147.)... Fig. 5.14. Separation of anilide derivatives of Cj -Cs straight-chain carboxylic acids. Peaks 1 = propionic 2 = n-butyric 3 = acetic 4 = n-valeric 5 = n-hexanoic 6 = formic and n-heptanoic 7 = n-octanoic acid STD = methyl myristate. Conditions glass column, 12 ft. x 3 mm I.D., 2.5% (w/w) sodium dodecylbenzene sulphonate on Chromosorb G (60-80 mesh, NAW) nitrogen inlet pressure, 15 p.s.i. temperature, 200°C. (Reproduced from/. Chromatogr., 51 (1970) 147.)...
This is evidenced by the values of pressure at which the CBF/NBF transition in NaDoS films occurs, n 9-104 Pa, since for sodium dodecylbenzene sulphonate films n is from 2 to 4104 Pa. Furthermore, the film radius in the latter case is larger, which can impede the precise identification of the metastable region of CBF/NBF transition (see Section 3.4.2). [Pg.199]

The purpose of this paper is to give a brief summary of an Investigation which has been carried out into the aqueous-phase polymerisation of butadiene initiated by cobalt(III) acetylacetonate In the presence of surfactants such as sodium dodecylbenzene-sulphonate and sodium decyl sulphate. It is Intended that fuller details of the investigation will be published elsewhere in due course. [Pg.162]

The polymerisation rate depends very much upon the nature of the surfactant used. In particular, reaction occurs more readily in the presence of sodium dodecylbenzene-sulphonate than in the presence of potassium oleate. [Pg.164]

Effect of surfactant level. Much of the earlier work on this reaction system was carried out using sodium dodecylbenzene-sulphonate as the surfactant. In the course of experiments which were Intended to investigate the effect upon polymerisation rate of varying the surfactant level, it was discovered that purified sodium dodecylbenzenesulphonates are apparently able to act as initiators of free-radical emulsion polymerisation in the absence of other added Initiating substances. Furthermore, as the results summarised in Figure 5 show, the rate of polymerisation in the absence of added initiator is directly proportional to the concentration of sodium dodecylbenzenesulphonate In the aqueous phase. [Pg.170]

The objective of the work is to present an experiment-founded adsorption model for precipitate flotation. Batch precipitate flotation of CufOH) with dodecylbenzene sulphonate (DBS) as collector, was carried out both with dissolved (DAF) and dispersed (DIS) air. The processes were considered as a succession of the dynamic equilibria taking place at the gasliquid and solidliquid interfaces. Both flotation processes were expressed quantitatively in terms of surface concentrations of Cu(OH)2 and DBS per unit surface area of the air buble, as well as the ratio of the numbers of air bubbles and solid particles (B /P ). Also the maximal concentrations of both DBS and Cu(OH)2, recoverable under the given conditions were calculated. All these values were determined by following the Cu(OH)2 and DBS recovery. The 2 flotation techniques were compared in regard to their efficiency and mechanism. Finally, the results obtained were discussed in terms of the other models for the colloid particle adsorption at the air-water interface. [Pg.311]

An International Symposium on Mining Research took place in 1961 (60) and was partly dedicated to AN—FO explosives. Hino and Yokogawa (61) described the action of sur/actants on the detonation ability of ammonium nitrate and its mixtures with coal tar in proportions 93.3/6.2- The addition of 0.55 of surfactant increased the detonation ability of the mixtures. Particularly effective were sodium dinaphthylmethane disulphonate, sodium laurylsulphon-ale and sodium dodecylbenzene sulphonate. [Pg.277]

Lee, H.-H. et al.. Dispersion of Fe3O4 suspensions using sodium dodecylbenzene sulphonate as dispersant. Mater. Lett., 61, 3974, 2007. [Pg.968]

Inoue K., Kaneko K. and Yoshida M. (1978) Adsorption of dodecylbenzene sulphonates by soil coUoids and influence of soil coUoids on their degradation. Soil Sci. Plant Nutr. 24, 91-102. [Pg.152]

An alternative anionic wetting agent is sodium dodecylbenzene sulphonate, with a branched alkyl chain... [Pg.259]

The anionic category represents the major part of surfactant consumption. Anionic surfactants include linear alkylbenzene sulphonates (LASs), alcohol sulphates or alcohol ethersulphates. The latter compounds have a poor absorption in the UV range, whereas the LASs show a significant absorption (see Chapter 11). Dodecylbenzene sulphonate (DBS) is used as a reference for LAS measurements (standard method) and shows an absorption band at 225 nm (Fig. 14). [Pg.101]

Dejing G, Na H, Yuan T, et al. Determination of bovine serum albumin using resonance light scattering technique with sodium dodecylbenzene sulphonate-cetyltrimethylammonium bromide probe. Spectrochim Acta A Mol Biomol Spectrosc 2007 3 573-7. [Pg.384]

Spontaneous emulsification requires a number of criteria that may be met by control of the properties of the interfacial region. Usually, a mixture of two or more emulsifiers are used, such as calcium dodecylbenzene sulphonate and an ethoxylated nonionic surfactant (2). With such blends, a 5% emulsifier concentration in the formulation may be sufficient for spontaneous emulsification and adequate stability within... [Pg.74]

Household detergents may contain 20-50% sodium triphosphate, together with comparatively small amounts of a long (carbon)-chain surface active agent such as sodium dodecylbenzene sulphonate,... [Pg.1058]

Sodium dodecylbenzene sulphonate Surface active agent 10... [Pg.1059]

Nacure 5225 is a blocked dodecylbenzene sulphonic acid cure catalyst made by King Industries. Surfonyl 465 is a surfactant produced by Air Products. [Pg.201]

Makowska, D., Sobczynska, A., Zimoch, J., Szymanowski, J. 2001. Interfacial activity of ethoxyethyl-ated fatty acid methyl esters. Mixtures with sodium dodecylbenzene sulphonate. Proceedings XXXI Jornadas Anuales del CID. Barcelona, 325-336. [Pg.284]

Dodecylbenzene sulphonate-doped PANINPs Ink-jet printing of chenucally polymerized NPs through a soft template substrate carbon-based electrode NH3 [123]... [Pg.153]

The first example of dihalocarbene insertion into a saturated C—H bond of an organometallic complex has been reported using a phase-transfer catalyst The first example of phase-transfer catalysts for electrophilic substitution involved an azo-coupling reaction in water-dichloromethane using sodium 4-dodecylbenzene-sulphonate giving a rate acceleration of ca. 200-fold. ... [Pg.346]

Ko et al. [110] have carried out electrochemical studies of chemically synthesized dodecylbenzene sulphonic acid (DBSA) doped polyaniline in a non-aqueous electrolyte such as propylene carbonate containing LiC104. According to these authors, electrochemical cycling of polymer films reduces the crystal-... [Pg.531]

Styrene (inhibitor free) Water (demineralized) Tricalcium phosphate Dodecylbenzene sulphonate Benzoyl peroxide... [Pg.74]

Stearate soaps Dodecyl sulphate Dodecylbenzene sulphonate Dioctyl sulphosuccinate Nonyl phenol polyether sulphate Dodecyl polyether phosphate Polyethoxylated alkanol Polyethoxylated nonyl phenol Polyethoxylated polypropylene glycol (pluronic) Glyceryl monolaurate... [Pg.220]

An interesting feature of the adsorption curves of many ionic surfactants is the occurrence of a distinct maximum in the isotherm at concentrations well in excess of the CMC. Such curves have been reported for the adsorption of sodium dodecyl sulphate and potassium myristate on graphite [60], sodium dodecyl sulphate on cotton and carbon [61,62] and sodium dodecylbenzene sulphonate on cotton, nickel and lead [63]. The striking decrease in the adsorption of sodium tetradecyl- and dodecyl sulphate on to porous glass (Fig. 1.11) at high concentra-... [Pg.24]

Cationic surfactant cetyl pyridinium chloride. Anionic sodium olefin dodecylbenzene sulphonate. Non-ionic octylphenyl polyoxyethylate surfactant. From [284]. [Pg.690]

The hydrolysis of carbohydrates in dodecylbenzene sulphonic acid in dioxane-water mixtures has been the subject of one study in which it Was found that the hydrolysis was accelerated by about 21 times in dioxane mixtures above 60% by volume [126], but no coherent mechanism was put forward for the catalysis. Non-ionic surfactants may form inverse micelles in non-aqueous solvents in the presence of small amounts of water. Triton X-1(X), for example, micellizes in carbon tetrachloride on addition of water. This system, which obviously does not suffer the problems which result from the dissociation of the head groups of ionic surfactants in the water pool, has been used to investigate the hydration reaction of acetaldehyde [127]. This acid-catalysed reaction is increased by a factor of 10000 over that in water (Table 11.9). In spite of the nonionic nature of the peripheral head groups surrounding and penetrating the aqueous core, the nature of the water is such that ionization of solubilized species is changed. [Pg.738]


See other pages where Dodecylbenzene sulphonate is mentioned: [Pg.587]    [Pg.157]    [Pg.467]    [Pg.321]    [Pg.96]    [Pg.107]    [Pg.2575]    [Pg.2576]    [Pg.232]    [Pg.587]    [Pg.1061]    [Pg.92]    [Pg.116]    [Pg.202]    [Pg.636]    [Pg.158]   
See also in sourсe #XX -- [ Pg.636 ]




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