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1D - Soil and Sediment Contamination (TUP/20) Desorption of PCBs from contaminated soils using perfluorinated surfactants solutions. Riaza-Frutos, Abel1, Ravina, Marta1, Manzano, Manuel1, Sibila-Lores, Miguel Angel1, Perales, Jose Antonio1, Quiroga, Jose Marķa1, 1 Dept. Chemical Engineering, and Environmental Technologies. Faculty of Marine and Environmental Sciences. University of Cadiz., Puerto Real, Cadiz, Spain ABSTRACT- Polychlorinated byphenils (PCBs) have been used during years without knowledge of their toxicity; they have been dispersed in the environment, being soils and sediments the main sinks. It is calculated that thousands of tons even remain, as well as the high thermal and chemical stability. A good technology to remediate PCBs contaminated soils is to extract them from soils with ex situ tecniques and later to degrade them with chemical and biological means. Due to the low solubility of PCBs, it is necessary to add some chemical compounds to enhance their solubility in water. This is the aim of this research: to extract PCBs using perfluorinated surfactants solutions for a later degradation treatment (i.e. Advanced Oxidation Processes). In this work, two differents perfluorinated surfactants have been tested, FT448 and FT800, which have differents physical and chemical properties. Different variables were tested such as shaking time, re-extractions, concentration of perfluorinated surfactant, etc. From the results obtained with both surfactants, it has optimized the best conditions (3 re-extractions of 30 minutes, concentration of perfluorinated surfactant of 1150 ppm and a mass of soil-volume of surfactant solution ratio of 1:10) and it has been selected FT800 perfluorinated surfactant (>90% of extraction) as the best one for extracting PCBs from contaminated soils. Key words: Soils, PCBs, Perfluorinated surfactants, Desorption |
