This study deals with the enhanced solubilization of polycyclic aromatic hydrocarbons （PAHs） such as phenanthrene （PHE） and fluorene （FLR） in a pure cationic gemini （G6） and three conventional surfactants [pol...This study deals with the enhanced solubilization of polycyclic aromatic hydrocarbons （PAHs） such as phenanthrene （PHE） and fluorene （FLR） in a pure cationic gemini （G6） and three conventional surfactants [polyethylene glycol dodecyl ether （Brij35）, cetyltrimethyl ammonium bromide （CRAB） and sodium lauryl sulfate （SDS）] as well as in their equimolar binary combinations （G6-Brij35, G6-CTAB and G6-SDS）. Their solubilization efficiency toward PHE and FLR has been quantified in terms of the molar solubilization ratio （MSR） and the micelle-water partition coefficient （Kin）. The ideality/nonideality of the mixed micelles is discussed with the help of Clint, Rubingh and Rosen＇s approaches. These theories determine the deviation of experimental critical micelle concen- tration （CMC） values from ideal critical micelle concentration, which was measured by evaluating the interaction parameters （/3m and/3）. Negative values ofβm were observed in all the equimolar binary systems, which show synergism in the mixed micelles. Whereas at air/liquid interface synergism was observed in the systems G6-CrAB and G6-Brij35; G6-SDS exhibited an antagonistic effect. The order of MSR and Km was G6-CTAB 〉 G6- Brij35 〉 G6-SDS for phenanthrene as well as for fluorene.展开更多
Experimental data are presented on the enhanced solubilities of fluorene (FLR) resulting from solubilization in aqueous solutions of two conventional surfactants: cationic cetyltrimethylammonium bromide (CTAB) , anion...Experimental data are presented on the enhanced solubilities of fluorene (FLR) resulting from solubilization in aqueous solutions of two conventional surfactants: cationic cetyltrimethylammonium bromide (CTAB) , anionic sodium dodecyl sulfate (SDS), nonioinic polyethylene glycol dodecyl ether (Brij35) and a cationic gemini bis (hexadecyldimethylammonium) pentane dibromide (G5). The critical micellar concentration of surfactants was determined by surface tension measurements and aqueous solubilities of fluorene compound in surfactant solutions were measured spectrophotometrically. Solubilization of PAH compound commenced at the surfactant critical micelle concentration and was proportional to the concentration of surfactant in micelle. The results of the mixed systems were analyzed with the help of regular solution theory, in which the deviation of CMCexp values for mixed surfactant systems from CMCideal was measured by evaluating the interaction parameter, βm. Negative values of βm were observed in all equimolar binary systems which show synergism in the mixed micelle. Attraction force between two oppositely charged head groups lead the strongest synergism effect between cationic gemini and anionic conventional surfactant. In addition to molar solubilization ratio (MSR) solubilization efficiency is also quantified in terms of micelle-water partition coefficient (Km).展开更多
文摘This study deals with the enhanced solubilization of polycyclic aromatic hydrocarbons （PAHs） such as phenanthrene （PHE） and fluorene （FLR） in a pure cationic gemini （G6） and three conventional surfactants [polyethylene glycol dodecyl ether （Brij35）, cetyltrimethyl ammonium bromide （CRAB） and sodium lauryl sulfate （SDS）] as well as in their equimolar binary combinations （G6-Brij35, G6-CTAB and G6-SDS）. Their solubilization efficiency toward PHE and FLR has been quantified in terms of the molar solubilization ratio （MSR） and the micelle-water partition coefficient （Kin）. The ideality/nonideality of the mixed micelles is discussed with the help of Clint, Rubingh and Rosen＇s approaches. These theories determine the deviation of experimental critical micelle concen- tration （CMC） values from ideal critical micelle concentration, which was measured by evaluating the interaction parameters （/3m and/3）. Negative values ofβm were observed in all the equimolar binary systems, which show synergism in the mixed micelles. Whereas at air/liquid interface synergism was observed in the systems G6-CrAB and G6-Brij35; G6-SDS exhibited an antagonistic effect. The order of MSR and Km was G6-CTAB 〉 G6- Brij35 〉 G6-SDS for phenanthrene as well as for fluorene.
文摘Experimental data are presented on the enhanced solubilities of fluorene (FLR) resulting from solubilization in aqueous solutions of two conventional surfactants: cationic cetyltrimethylammonium bromide (CTAB) , anionic sodium dodecyl sulfate (SDS), nonioinic polyethylene glycol dodecyl ether (Brij35) and a cationic gemini bis (hexadecyldimethylammonium) pentane dibromide (G5). The critical micellar concentration of surfactants was determined by surface tension measurements and aqueous solubilities of fluorene compound in surfactant solutions were measured spectrophotometrically. Solubilization of PAH compound commenced at the surfactant critical micelle concentration and was proportional to the concentration of surfactant in micelle. The results of the mixed systems were analyzed with the help of regular solution theory, in which the deviation of CMCexp values for mixed surfactant systems from CMCideal was measured by evaluating the interaction parameter, βm. Negative values of βm were observed in all equimolar binary systems which show synergism in the mixed micelle. Attraction force between two oppositely charged head groups lead the strongest synergism effect between cationic gemini and anionic conventional surfactant. In addition to molar solubilization ratio (MSR) solubilization efficiency is also quantified in terms of micelle-water partition coefficient (Km).
