Dodecylpyridinium

Dodecylpyridinium chloride [104-74-5] M 301.9, m 68-70". Purified by repeated crystn from acetone (charcoal) twice recrystd from EtOH [Chu and Thomas 5 Am Chem Soc 108 6270 1986],... 

Dodecylpyridinium iodide-reversed micelles trapping chlorophyll a have been suggested as interesting photochemical model systems [22] and water/AOT/chloroethylene systems as peculiar dry-cleaning solvents [64]. 

Surfactants greatly improve the performance of trans-cinnamaldehyde as a corrosion inhibitor for steel in HCl [741,1590,1591]. They act by enhancing the adsorption at the surface. Increased solubility or dispersibility of the inhibitor is an incidental effect. N-dodecylpyridinium bromide is effective in this aspect far below its critical micelle concentration, probably as a result of electrostatic adsorption of the monomeric form of N-dodecylpyridinium bromide. This leads to the formation of a hydrophobic monolayer, which attracts the inhibitor. On the other hand, an ethoxylated nonylphenol, a nonionic surfactant, acts by incorporating the inhibitor into micelles, which themselves adsorb on the steel surface and facilitate the adsorption of trans-cinnamaldehyde. 

Mixtures of aldehydes with surfactants are active in preventing corrosion, in particular in the presence of mineral or organic acids [646]. The aldehyde may be trans-cinnamaldehyde. The surfactant may be N-dodecylpyridinium bromide or the reaction product of trimethyl-1-heptanol with ethylene oxide [645]. Such aldehyde and surfactant mixtures provide greater and more reliable corrosion inhibition than the respective compositions containing aldehydes alone. 

Harada, S. and Schelly, Z. A. (1982). Reversed micelle of dodecylpyridinium iodide in benzene. Pressure-jump relaxation kinetic and equilibrium study of the solubilization of 7,7,8,8-tetracyanoquinodimethane. J. Phys. Chem., 86, 2098-102. 

Figure 11.15 Observed sorption of dodecylpyridinium on a soil (EPA-12) exhibiting an overall cation exchange capacity of 0.135 mol-kg"1. Two Langmuir isotherms (defined with particular values of C,s max and K/l, recall Eq. 9-5) are placed on the data to illustrate how different portions of the observed isotherm may reflect the influence of different materials in the complex soil sorbent or possibly different mechanisms (data from Brownawell et al., 1990).

Figure 18.11 (a) Osmotic coefficient (b) apparent relative molar enthalpy (c) apparent molar volume and (d) apparent molar heat capacity, at T = 298.15 K and p = 0.1 MPa, for (1) n-decylpyridinium chloride and (2) n-dodecylpyridinium chloride. 

The effect of temperature on the thermodynamic properties and the CMC is shown in Figure 18.13, where 4>L, < >CP and (f>V at three temperatures are graphed as a function of the molality m for n-dodecylpyridinium chloride. We can interpolate the results in Figure 18.13a to determine that L at the CMC is near zero for this surfactant at a temperature near, but just above, 298.15 K. When 4>L = 0, the CMC is at its minimum value. We will better understand why as we consider theories for describing the curves shown in Figures 18.11 and 18.13. 

Figure 18.13 Effect of temperature on (a) apparent relative molar enthalpies (b) apparent molar volumes and (c) apparent molar heat capacities, for n-dodecylpyridinium chloride. The temperatures are (1) 298.15 K (2) 313.15 K and (3) 328.15 K.

The thermodynamic properties at T = 298.15 K shown in Figure 18.11 come from S. Causi, R. De Lisi, and S. Milioto, Thermodynamic properties of N-octyl-, N-decyl- and N-dodecylpyridinium chlorides in water , J. Solution Chem., 20, 1031-1058 (1991). Results at the other two temperatures are courtesy of K. Ballerat-Busserolles, C. Bizzo, L. Pezzimi, K. Sullivan, and E. M. Woolley, Apparent molar volumes and heat capacities at aqueous n-dodecyclpyridium chloride at molalities from 0.003 molkg-1 to 0.15 molkg-1, at temperatures from 283.15 K. to 393.15 K, and at the pressure 0.35 MPa , J. Chem. Thermodyn., 30, 971-983 (1998). 

Hydrotalcite is often too fine grained to produce treatment columns with suitable permeability. As an alternative, the sorbent may be mixed with contaminated water in a tank (Lazaridis et al, 2002). The spent sorbent is then separated from the treated water by flocculation, flotation, or other separation methods (see Section 7.2.4). Lazaridis et al. (2002) investigated the use of surfactants with dispersed-air flotation to separate spent hydrotalcites from treated water. At ionic strengths of 0.1 M using KNO3, effective flotation and separation could be obtained by using a mixture of dodecylpyridinium chloride, sodium dodecylhydrogen sulfate, and a cetyltrimethyl ammonium bromide frother (Lazaridis et al., 2002,322,323). 

Hermann, R., Gerke, J. and Ziechmann, W. (1997) Photodegradation of the surfactants Na-dodecylbenzenesulfonate and dodecylpyridinium-chloride as affected by humic substances. Water Air Soil Pollut. 98,43-55... 

Membrane from a 5% NA cellulose sulfate solution and 20% 0% solutions of cationic surfactants e.g., V-dodecylpyridinium chloride or hexadecylpridinium chloride Hybrid PV + distillation systems... 

Cationic counter-ion N-Dodecylpyridinium chloride silanized silicagel... 

Cyclic alkylammonium compounds resemble the linear products in their properties. They are widely found in antiseptic solutions, cremes, shampoos, and mouthwashes. As an example for this class of compounds, Fig. 5-48 displays the chromatogram of a dodecylpyridinium chloride. Its individual components, with the exception of the main component, exhibit a similar retention behavior to that of Benzalkon A. The minor components of this sample are presumably tetradecyl- and hexadecylpyridinium chloride. 

Fig. 5-48. Separation of dodecylpyridinium chloride. - Separator column IonPac NS1 (10 pm) eluent 0.02 mol/L HC1 / acetonitrile (24 76 v/v) flow rate 1 mL/min detection UV (215 nm) injection volume 50 pL solute concentration 100 mg/L raw material.

Analysis of the quenching data of pyrene fluorescence by 1-dodecylpyridinium chloride, DPC via pulsed laser studies confirms the Poisson distribution of DPC amongst the aggregates. Figure 10A shows the excellent fit of the Poisson kinetics to the time -dependent quenching of Pyrene fluorescence in deaerated aqueous... 

Although most of the times it is of interest to obtain stable mesophases, it may be useful also to exploit their controlled degradation or transformation. Taubert and coworkers reported a very interesting application of metallomesogens [80, 81]. They prepared mixtures of bis(dodecylpyridinium) tetrachlorocuprate 37 and of... 

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