Dodecane-, sodium

Danes PR, Vandegrift GF (1991) Kinetics and mechanism of the interfacial mass transfer of europium(3+) and ameiicium(3+) in the system bis(2-ethylhexyl)-phosphate-n-dodecane-sodium chloride-hydrochloric acid-water. J Phys Chem 39 1425-1432... 

Fig. III-9. Representative plots of surface tension versus composition, (a) Isooctane-n-dodecane at 30°C 1 linear, 2 ideal, with a = 48.6. Isooctane-benzene at 30°C 3 ideal, with a = 35.4, 4 ideal-like with empirical a of 112, 5 unsymmetrical, with ai = 136 and U2 = 45. Isooctane-

Figure 20 shows the plot of the surface tension vs. the logarithm of the concentration (or-lg c-isotherms) of sodium alkanesulfonates C,0-C15 at 45°C. In accordance with the general behavior of surfactants, the interfacial activity increases with growing chain length. The critical micelle concentration (cM) is shifted to lower concentration values. The typical surface tension at cM is between 38 and 33 mN/m. The ammonium alkanesulfonates show similar behavior, though their solubility is much better. The impact of the counterions is twofold First, a more polarizable counterion lowers the cM value (Fig. 21), while the aggregation number of the micelles rises. Second, polarizable and hydrophobic counterions, such as n-propyl- or isopropylammonium and n-butylammonium ions, enhance the interfacial activity as well (Fig. 22). Hydrophilic counterions such as 2-hydroxyethylammonium have the opposite effect. Table 14 summarizes some data for the dodecane 1-sulfonates.

FIG. 20 CT-lg c Isotherms of homologous sodium alkane 1-sulfonates in water at 45 °C. , Decane 1-sulfonate , dodecane 1-sulfonate , tridecane 1-sulfonate a, tetradecane 1-sulfonate x, pentadecane 1-sulfonate. 

FIG. 23 CT-lg c Isotherms for sodium alkanesulfonates with the functional group in different positions, x, Dodecane 1-sulfonate (45°C) , dodecane 5-sulfonate (25°C) , pentadecane 1-sulfonate (45°C) , pentadecane 8-sulfonate (45°C). 

Sodium dodecane sulfonate Dodecyl triethylene glycol ether -3.2 -2.6... 

Sodium dodecane sulfonate A-Dodecyl-A-benzyl-A-methylglycine -6.9 -5.4... 

An example for a partially known ternary phase diagram is the sodium octane 1 -sulfonate/ 1-decanol/water system [61]. Figure 34 shows the isotropic areas L, and L2 for the water-rich surfactant phase with solubilized alcohol and for the solvent-rich surfactant phase with solubilized water, respectively. Furthermore, the lamellar neat phase D and the anisotropic hexagonal middle phase E are indicated (for systematics, cf. Ref. 62). For the quaternary sodium octane 1-sulfonate (A)/l-butanol (B)/n-tetradecane (0)/water (W) system, the tricritical point which characterizes the transition of three coexisting phases into one liquid phase is at 40.1°C A, 0.042 (mass parts) B, 0.958 (A + B = 56 wt %) O, 0.54 W, 0.46 [63]. For both the binary phase equilibrium dodecane... 

The HLB numbers decrease with increasing chain length, e.g., from 13.25 for sodium decane 1-sulfonate to 9.45 for the C18 homolog [72]. Typical HLB numbers for positional isomers range from 12.3 for sodium dodecane 1-sulfonate to 13.2 for the more hydrophilic 6 isomer [73]. The HLB numbers of alkanesulfonates are less influenced by the isomeric position of the functional group and by substituents than the cM values [68]. HLB numbers can be correlated with partition coefficients for the distribution of a surfactant between the aqueous and oily phases, which emphasizes that the partition coefficient is dependent on the carbon number [68]. 

A study using resuspended river sediment (Marchesi et al. 1991) illustrated the important interdependence of substrate attachment to particulate matter and its biodegradability. Addition of sodium dodecyl sulfate that is degradable resulted in a relative increase in the number of particle-associated bacteria, whereas this was not observed with the nondegrad-able analogs such as sodium tetradecyl sulfate or sodium dodecane sulfonate. 

Since there would be increased overall lipid concentration in the dodecane solution, we decided to create a sink condition in the acceptor wells, to lower the membrane retention. We discovered that the pH 7.4 buffer saturated with sodium laurel sulfate serves as an excellent artificial sink-forming medium. Since the new PAMPA membranes would possess substantial negative charge, the negatively charged micellar system was not expected to act as an aggressive detergent to the two-component artificial membrane infused in the microfilter. 

The reverse emulsion stabilized by sodium dodecylsulfate (SDS, R0S03 Na+) retards the autoxidation of dodecane [24] and ethylbenzene [21,26,27]. The basis for this influence lies in the catalytic decomposition of hydroperoxides via the heterolytic mechanism. The decay of hydroperoxides under the action of SDS reverse micelles produces olefins with a yield of 24% (T=413 K, 0.02mol L 1 SDS, dodecane, [ROOH]0 = 0.08 mol L 1) [27], The thermal decay gives olefins in negligible amounts. The decay of hydroperoxides apparently occurs in the ionic layer of a micelle. Probably, it proceeds via the reaction of nucleophilic substitution in the polar layer of a micelle. 

The protocol consisted of preconditioning with methanol (1 mL) followed by water (1 mL). Urine samples (3 mL) were deconjugated by treatment with /3-glucuronidase and arylsulfatase (10 jt/L and 200 fig/fiL) in 0.1M sodium acetate (pH 5.5) and then loaded onto conditioned cartridges. After washing with water (1 mL) and methanoksodium acetate (3 mL, 4 6, pH 5.5), the PAH metabolites were eluted with dichloromethane (3 mL). The eluate was spiked with dodecane (used... 

REDUCTION OF ALKYL HALIDES AND TOSYLATES WITH SODIUM CYANOBOROHYDRIDE IN HEXAMETHYL-PHOSPHORAMIDE (HMPA) A. 1-IODODECANE TO n—DECANE B. 1-DODECYL TOSYLATE TO n-DODECANE, 53, 107 REDUCTION OF KETONES BY USE OF TOSYLHYDRAZONE DERIVATIVES ANDROSTAN-17 0—OL, 52, 122 REDUCTIVE AMINATION WITH SO-... 

AH operations should be carried out under an atmosphere of nitrogen in a thoroughly dried apparatus. The hydrocarbon solvents, dodecane, tridecane, and hexane, must be dried over sodium dichloromethane should be distilled from CaH2 (or dried over 4A molecular sieves). 

B. Reduction of 1-Dodecyl Tosylate to n-Dodecane. In a dry 200-ml. three-necked flask equipped exactly as described in Section A are placed 50 ml. of hexamethylphosphoramide (HMPA), 1-dodecyl tosylate (6.80 g., 0.0201 mole) (Note 8), and sodium cyanoborohydride (5.02 g., 0.080 mole) (Note 3). The solution is stirred at 80° for 12 hours (Note 9), then diluted with 50 ml. of water, and extracted with three 60-ml. portions of hexane. The hexane solution is washed twice with water, dried over anhydrous magnesium sulfate, and then concentrated at reduced pressure with a rotary evaporator. Distillation of the residue through a short-path apparatus (Note 5) (Cautionl foaming) affords 2.49-2.64 g. (73-78%) of w-dodecane, b.p. 79-81° (3.75 mm.) na4D 1.4217 (lit.,3 n20d 1.4219) (Note 7). 

The symmetrical Wurtz coupling has been found to give particularly good yields in the case of the higher alkane homologues. Selected illustrative examples (hexane, octane, decane and dodecane) are to be found in Expt 5.7. A related reaction is to be found in the synthesis of hexa- 1,5-diene (Expt 5.7, cognate preparation), which illustrates the symmetrical coupling of two molecules of allyl iodide by the action of sodium metal. 

The SETFICS process (Solvent Extraction for Trivalent /-elements Intragroup Separation in CMPO-Complexant System) was initially proposed by research teams of the former Japan Nuclear Cycle Development Institute (JNC, today JAEA) to separate An(III) from PUREX raffinates. It uses a TRUEX solvent (composed of CMPO and TBP, respectively dissolved at 0.2 and 1.2 M in -dodecane) to coextract trivalent actinides and lanthanides, and a sodium nitrate concentrated solution (4 M NaN03) containing DTPA (0.05 M) to selectively strip the TPEs at pH 2 and keep the Ln(III) extracted by the TRUEX solvent (239). However, the DFs for heavy Ln(III) are rather poor. An optimized version of the SETFICS process has recently been proposed as an alternative process to extraction chromatography for the recovery of Am(III) and Cm(III) in the New Extraction System for TRU Recovery (NEXT) process. NEXT basically consists of a front-end crystallization of uranium, a simplified PUREX process using TBP for the recovery of U, Np, and Pu, and a back-end Am(III) + Cm(III) recovery step (240, 241). 

Fuerstenau, D.W., and Wakamatsu T. (1975). Effect of pH on the adsorption of sodium dodecane sulphonate at the alumina/water interface. Faraday Discussions of the Chemical Society, 59, 157-168. 

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