[article]
Titre : |
Octanol-water partition coefficients of surfactants : slow stirring/surface tension method |
Type de document : |
texte imprimé |
Auteurs : |
D. J. Miller, Auteur ; P. McWilliams, Auteur |
Année de publication : |
2010 |
Article en page(s) : |
p. 28-33 |
Note générale : |
Bibliogr. |
Langues : |
Anglais (eng) |
Tags : |
Log P Surface tension Bioaccumulation Anionic surfactant |
Index. décimale : |
668.1 Agents tensioactifs : savons, détergents |
Résumé : |
A slow stirring method to measure log P values of water-soluble surfactants is described. Aqueous surfactant solution is equilibrated with octanol. A surface tension technique is used to determine the decrease in concentration in the aqueous phase. Interference from octanol, which is surface active, is prevented by evaporation and redissolution of the sample. For industrial surfactants this method gives a log P value that is effectively weighted according to the surface activity of the components. The test can be used to screen surfactants for a possible risk of bioaccumulation as it is generally accepted that substances with log P < 3 are unlikely to bioaccumulate. The apparent log P of an alkane sulfonate was 1.5 when a 1 g/L aqueous solution was equilibrated with an equal volume of octanol. Due to ion pair formation in the octanol phase the apparent log P decreased with concentration. As a result, the tendency to partition into octanol is likely to be less at environmentally relevant concentrations. |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=8067 |
in TENSIDE, SURFACTANTS, DETERGENTS > Vol. 47, N° 1/2010 (01-02/2010) . - p. 28-33
[article]
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