Alkyl ethoxylates

Fatty alcohol- (or alkyl-)ethoxylates, CoE, are considered to be better candidates for LLE based on their ability to induce rapid phase separation for Winsor II and III systems. (Winsor III systems consist of excess aqueous and organic phases, and a middle phase containing bicontinuous microemulsions.) However, C,E,-type surfactants alone cannot extract biomolecules, presumably because they have no net negative charge, in contrast to sorbitan esters [24,26,30,31]. But, when combined with an additional anionic surfactant such as AOT or sodium benzene dodecyl sulfonate (SDBS), or affinity surfactant, extraction readily occurs [30,31]. The second surfactant must be present beyond a minimum threshold value so that its interfacial concentration is sufficiently large to be seen by... 

CnH2n+i-0-(CH2-CH2-0)x-S03 now could be observed as [M + NH4]+ ions at a RTof 3.8-5.0 min. Signal intensity was quite low but a wide range of alkyl ethoxylated sulfate compounds, starting at m/z 372 and ending at 680 and AES ammonium adduct ions with 3-10 EO units were recorded. With an elevated intensity as observed under APCI(+) ionisation, the [M + NH4]+ions of the non-ionics AEhomologue mixture were observed in Fig. 2.5.11(b) at a RT of 7-10 min. 

Despite the fact that physico-chemical and chemical degradations were not possible, the isolation of persistent metabolites of the CnF2n+i-(CH2-CH2-0)m-H compound generated by (3 and w oxidations of the terminal PEG unit of the non-ionic blend was reported, but environmental data about this type of compound are still quite rare [49]. TSI(+) ionisation results of the industrial blend Fluowet OTN have been reported in the literature [7,51]. Actual data of non-ionic fluorinated surfactants were applied using ESI- and APCI-FIA-MS(+) and -MS-MS(+), which reported the biodegradation of the non-ionic partly fluorinated alkyl ethoxylate compounds C F2 fi-(CH2-CH2-0)x-H in a lab-scale wastewater treatment process. 

Among the purposes of this paper is to report the results of calorimetric measurements of the heats of micellar mixing in some nonideal surfactant systems. Here, attention is focused on interactions of alkyl ethoxylate nonionics with alkyl sulfate and alkyl ethoxylate sulfate surfactants. The use of calorimetry as an alternative technique for the determination of the cmc s of mixed surfactant systems is also demonstrated. Besides providing a direct measurement of the effect of the surfactant structure on the heats of micellar mixing, calorimetric results can also be compared with nonideal mixing theory. This allows the appropriateness of the regular solution approximation used in models of mixed micellization to be assessed. 

It is clearly seen that the interaction of SDS with C] oE5 is significantly stronger than that of the alkyl ethoxylate sulfate surfactants with C] oE5 In addition, the symmetry in the heat of mixing curves is strikingly different with those for C] 2 2 Cj qEjS showing an asymmetric maximum at about a... 

Calorimetric measurements can be used to obtain heats of mixing between different surfactant components in nonideal mixed micelles and assess the effects of surfactant structure on the thermodynamics of mixed micellization. Calorimetry can also be successfully applied in measuring the erne s of nonideal mixed surfactant systems. The results of such measurements show that alkyl ethoxylate sulfate surfactants exhibit smaller deviations from ideality and interact significantly less strongly with alkyl ethoxylate nonionics than alkyl sulfates. 

Nonionic surfactants are also used in substantial amounts in laundry detergents and in automatic dishwashing detergents, both applications reflecting in particular their generally lower sudsing characteristics than the anionics. Commercially important examples uf the nonionics include the alkyl ethoxylates, the ethoxylated alkyl phenols, the fatly acid ethanol amides, and complex polymers of ethylene oxide, propylene oxide, and alcohols. 

Ferguson et al. [52] compared the behavior of a range of conventional alkyl ethoxylate surfactants in emulsion polymerizations with their acrylated analogues. This has allowed a direct comparison of identical surfactant structures, one of which remains kinetically mobile in the resultant lattices, while the other becomes chemically bound to the latex particles. The surfactants chosen for this study were C12 i4-(EO)30 with C12 14-(EO)30-A and C12 14-(EO)12 with C12 14-... 

NX - - BENZENESULFONIC ACID, ALKYL deriv. and TALLOW ALKYL ETHOXYLATE SULFATE... 

Goda, Y., M. Hirobe, A. Kobayashi, et al. 2005. Production of a monoclonal antibody and development of enzyme-linked immunosorbent assay for alkyl ethoxylates. Anal. Chim. Acta 528 47-54. 

Gas chromatography has been applied to the determination of a wide range of organic compounds in trade effluents including the following types of compounds which are reviewed in Table 15.15 aromatic hydrocarbons, carboxylic acids aldehydes, non ionic surfactants (alkyl ethoxylated type) phenols monosaccharides chlorinated aliphatics and haloforms polychlorobiphenyls chlorlignosulphonates aliphatic and aromatic amines benzidine chloroanilines chloronitroanilines nitrocompounds nitrosamines dimethylformamide diethanolamine nitriloacetic acid pyridine pyridazinones substituted pyrrolidones alkyl hydantoins alkyl sulphides dialkyl suphides dithiocaibamate insecticides triazine herbicides and miscellaneous organic compounds. 

TTAB, in combination with an alkyl ethoxylated sulfate, also lowers the surface tension observed at CMC by approximately 10 dyne cm-1 compared to either of the surfactants alone. It is postulated that the combination of the anionic and cationic results in charge neutralization providing a net surfactant which is similar to a nonionic surfactant. This is confirmed by the lowering of the cloud point of the surfactant combination as the mole fraction of anionic and cationic are adjusted to near the equivalency point. 

Ferguson, R, Sherrington, D.C. and Gough, A. (1993) Preparation, characterization and use in emulsion polymerization of acrylated alkyl ethoxylate surface-active monomers. Polymer, 34, 3281-92. 

Pesticide residues Acetochlor Alachlor Atrazine Carbendazin/Benomyl Cyclodienes, 2,4-D DDE Diuron Glyphosate Metolachlor Organophosphate/Carbamate Pyrethroids Spynosyn Surfactants Alkyl ethoxylate (AE) Alkylphenol ethoxylate (APE) Linear alkylbenzene sulfonate (LAS) Estrogens 17-B-Estradiol (E2) ... 

A series of related experiments investigated nonionic surfactant sorption onto soil, mechanisms of nonionic surfactant solubilization of polycyclic aromatic hydrocarbon (PAH) compounds from soil, and microbial mineralization of phenanthrene in soil-aqueous systems with nonionic surfactants. Surfactant solubilization of PAH from soil at equilibrium can be characterized with a physicochemical model by using parameters obtained from independent tests in aqueous and soil-aqueous systems. The microbial degradation of phenanthrene in soil-aqueous systems is inhibited by addition of alkyl ethoxylate, alkylphenyl ethoxylate, or sorbitan- (Tween-) type nonionic surfactants at doses that result in micellar solubilization of phenanthrene from soil. Available data suggest that the inhibitory effect on phenanthrene biodegradation is reversible and not a specific, toxic effect. 

Engelskirchen, S., Eisner, N., Sottmann, T. and Strey, R. (2007) Triacylglycerol microemulsions stabilized by alkyl ethoxylate surfactants - A basic study Phase behaviour, interfacial tensions and microstructure. /. Colloid Interface Sci., 312, 114-121. 

Arol Defoamer. [Atol Chem. Prods.] Complex alkyl ethoxylate blend defoamer. 

Liptol. [Lion] Alkyl ethoxylate deinking agent for flotadon processes. 

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