Dodecane, physical properties

Physical properties of pure TBP have been given in Table 4.5. Physical properties of n-dodecane and a 30 v/o solution of TBP in n-dodecane are summarized in Table 10.13. 

In summary, electrostatic repulsion stabilizes lamellar phases in ionic systems, whereas entropy reduction stabilizes lamellar phases in nonionic systems or in ionic systems in apolar solvents or in high ionic strength water. Also, the presence of suitable cosurfactants (generally alcohols), which increase the flexibility of the membranes, leads to the formation of dilute lamellar phases, for example, in the system brine-SDS-pentanol [133] or brine-SDS-pentanol-dodecane [134]. Recently, it was shown [135] that two distinct lamellar phases coexisted in the dilute region of the system cetylpyridinium chloride-hexanol-brine. The two phases differ in turbidity, viscosity, density, and some other physical properties. One of these lamellar phases is classically stabilized by the competition between van der Waals, hydration, and electrostatic forces. The other phase is entropically stabilized. The difference between electrostatically and sterically stabilized lamellar phases was demonstrated by transmission electron microscopy on thin vitrified... 

With all these factors in mind, we have attempted to carry out the emulsions aspect of the investigations at the University of Florida Improved Oil Recovery Research Program (4,5). The emulsion systems contain TRS 10-410, isobutanol, sodium chloride, dodecane and water. Extensive physical property data and micro-structural studies of the aqueous surfactant formulations have been already reported by Vijayan et al. (6). Also, the structural aspects of the emulsions containing the same species with aqueous to oil ratio of 1 1 as well as various physical property data as a function of salt concentration have been reported by Vijayan et al. (7). A detailed study of the middle phases formed by the same surfactant formulation with dodecane oil with respect to microstructural changes and microemulsion (swollen micelle) phase inversion has been reported by Ramachandran et al. (8). 

Physical properties Pentane Hexane Heptane Octane Nonane Decane Dodecane... 

This constancy may at first seem remarkable, but it is to be expected if one keeps in mind the fact that hydrocarbons axe essentially long chains of CHs groups. Consider two hypothetical crude oils, one consisting of pure octane (CgHis) fl-nd the second of pure dodecane (CxaHso). Tlrese two crudes would have entirely different physical and chemical properties. The first would be an excellent gasoline, whereas the second would have the properties of kerosene. However,... 

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