Chemical compatibility testing of geomembranes – sorption/desorption, diffusion, permeation and swelling phenomena

The laboratory test results of 14 organic liquids (widely varying in nature) for high density polyethylene, linear low density polyethylene, very low density polyethylene and polypropylene geomembranes are presented at 25, 50 and 70°C. The partition coefficients have been calculated by monitoring the increase in mass of geomembrane immersed in the fluid of interest from its initial value until the mass of geomembrane becomes constant. From such data, diffusion and permeation coefficients have been calculated using Fick's equation from the initial linear portions of the sorption curves. Swelling of the geomembranes has also been studied from a measurement of an increase in volume, thickness and diameter. From a temperature dependence of sorption, diffusion and permeation coefficients, the Arrhenius parameters have been calculated.