Prediction of the behaviour of organic pollutants using cloud point extraction.
A preconcentration study based on the cloud point phenomenon was carried out for a set of triazine herbicides, three of them chloro-substituted and three of them methylthio-substituted. Concentration factors and recoveries were calculated as function of the percentage of the non-ionic surfactant Triton X-114 employed. From these values, obtained from a cloud point extraction (CPE) procedure, the distribution coefficient between the Triton X-114 micelles and water, Kc, prior to CPE was calculated for each triazine and related to the corresponding octanol-water partition coefficient, Kow. In order to confirm the results obtained with the triazine herbicides, two sets of data from chemically different organic pollutants--organophosporous and chlorophenols--obtained from the literature were assessed, concluding that they display a similar behaviour to that of the triazine herbicides. This can be used to predict the CPE behaviour of other organic pollutants from their octanol-water partition coefficients. The Kc values were compared with the analyte concentration ratio in the surfactant-rich phase and aqueous phase (Ksa) with a view to obtaining a link between the analyte behaviour prior to and after cloud point extraction procedures.
Carabias-Martínez
R
R
Departamento de Química Analítica, Nutrición y Bromatología, Facultad de Química, Universidad de Salamanca, Plaza de la Merced s/n, 37008 Salamanca, Spain. rcm@usal.es
Rodríguez-Gonzalo
E
E
Domínguez-Alvarez
J
J
García Pinto
C
C
Hernández-Méndez
J
J
D004785:Environmental Pollutants / Q000032:analysis*; D006540:Herbicides / Q000032:analysis*; D014227:Triazines
D004785:Environmental Pollutants; D006540:Herbicides; D014227:Triazines