Chemical compatibility study of geomembranes - sorption/desorption, diffusion and swelling phenomena

Sorption/desorption results of n-alkanes into high density polyethylene, Linear low density polyethylene, very low density polyethylene and polypropylene geomembranes are presented at 25, 50 and 70 degrees C. Sorption results are obtained by a gravimetric method and diffusion coefficients have been calculated by using Fick's equation from the initial linear portions of the sorption/desorption curves. Swelling of the geomembranes was studied from a measurement of the increase in volume, thickness and diameter. From a temperature dependence of sorption and diffusion coefficients, the Arrhenius parameters have been calculated. Liquid-concentration profiles have been computed using Fick's equation for the appropriate initial and boundary conditions. The results of this study may have relevance in selecting the suitable geomembrane for a specific application in hazardous waste chemical ponds and other similar situations. (C) 1998 Elsevier Science B.V. All rights reserved.