Bulk fluid phase - mesophase systems

Such a micelle acts like an oil drop in an aqueous solution and allows solubilization of organic compounds present in the aqueous solution into the hydrophobic interior. If the surfactant is ionic, i.e. either cationic or anionic, then oppositely charged ionic species, namely counterions from the solution, will be adsorbed on the surface of the micelle or bind with the charged micellar surface. Such surfrice binding will effectively Increase the micelle dimension. A unique number of surfrictant molecules between 50 and 100 aggregate to form a micelle. 

The partitioning of a solute between the micelle (interior for uncharged species, exterior for charged species) has been described in a number of ways, including the equilibrium ratio Kj, the distribution coefScient Ka, etc. One method of description for uncharged organic solutes used by a number of investigators defines a solubilization 

BsAeEg 5 Bs is a branched hydrocarbon chain, A is a six-carbon aromatic ring E9.5 is 9.5 repeating -CH2CH2O- group (mol.wt 628). 

9 Partitioning between a bulk fluid phase and an individual molecule/macromoleimle or a ixillection of molecules for nonixivalent solute binding 

A variety of chemical interactions are possible between two molecules of two different species. Those that result in chemical reactions are considered in Chapter 5 for the purpose of separation of mixtures. There are a number of other, weaker, noncovalent interactions where the bond energy is less than 50 Id/mol. These include chelation, clathration, hydrogen bonding, hydrophobic interactions, ionic binding, pi bonding, van der Waals interactions, etc. These result in weak chemical complexes, which are 

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