Removal of polycyclic aromatic hydrocarbons from water by migration into polyethylene

Water was spiked with three polycyclic aromatic hydrocarbons (PAHs) and fil led into a steel diffusion chamber. Low-density polyethylene sheet combined of live polyethylene foils was used as a partition in the chamber. Depth o f PAHs migration into the sheet was followed for 143 h, using high performa nce liquid chromatography with selective fluorimetric detection after extra ction of PAHs from the foils peeled off. On the basis of the results obtain ed, the process of PAHs migration into PE was characterised as a one-dimens ional diffusion into polyethylene bulk. The diffusion coefficients were cal culated for individual compounds using the second Fick law. It was conclude d that PAHs are primarily adsorbed on the polyethylene surface with subsequ ent migration into bulk polymer. Transportation of PAHs through the bulk ca n be described satisfactorily by Fickian laws of diffusion and is consisten t with the theory of the depth adsorption of PAHs in polyethylene. (C) 1998 Elsevier Science Ltd. All rights reserved.