Studies On The Solubilization Of Polycyclic Aromatic Hydrocarbons By Single And Mixed Surfactants

Mechanism, description methods and influencing factors of solubilization, principle and types of mixed surfactants, and the application of surfactant enhanced remediation (SER) in repairing polycyclic aromatic hydrocarbons (PAHs) pollution were emphatically discussed.Solubilization of phenanthrene and pyrene by gemini surfactant CG12-2-12, nonionic surfactants (TritonX-100, Brij35, and Tween80), and mixed surfactant systems of CG12-2-12/TritonX-100, CG12-2-12/Brij35 and CG12-2-12/Tween80 were studied. The solubilization capacities of single and mixed surfactant systems on phenanthrene and pyrene were evaluated through the critical micelle concentration (CMC), the molar solubilization ratio (MSR) and the micelle-aqueous phases partition coefficient (Kmc). The results showed that the solubilization ability of mixed surfactants were larger than single surfactant, showing synergistic solubilization effect. And all the mixed surfactant systems showed greater synergistic solubilization ability on pyrene than on phenanthrene. It is demonstrated that there is a positive correlation with the hydrophobic of polycyclic aromatic hydrocarbons (PAHs). The interaction parameterβ,the ratio (B) of CMCexp vs CMCideal and the ratio (R) of MSRexp vs MSRideal were analyzed to to interpret the mutual influence between mixed surfactant systems.The solubilization ability of single and mixed gemini surfactant (CG12-2-12) and nonionic surfactant (Brij35) systems on phenanthrene with naphthalene or pyrene coexisted were observed. The results.showed that there were competed interaction between phenanthrene and pyrene in the CG12-2-12 surfactant system, and there were synergic interaction between phenanthrene and coexist PAHs at a certain extent in other mixture of surfactant and PAHs. However, the degree of synergic influence in CG12-2-12/Brij35 mixed surfactants system was greater than every single surfactant system.The influence factor of solubilization of phenanthrene by CG12-2-12/Brij35 mixed surfactants system, such as molar ratio, inorganic electrolyte and temperature, were analytically studied. The result proved that the 1:9 was the optimal mixing proportion of CG12-2-12 surfactant with Brij35 surfactant, where showed good synergetic solubilization effect. There was a certain degree of influence of inorganic electrolyte on solubilization and the effect sequence of cationic was Mg2+>Ca2+>K+>Na+. The solubilization ability of phenanthrene in mixed surfactant system was significantly increased with temperature elevated.