DIFFUSION AND SORPTION OF ORGANIC KETONES AND NITRILES INTO TETRAFLUOROETHYLENE PROPYLENE COPOLYMERIC MEMBRANES/

Diffusion and sorption of acetonitrile, acrylonitrile, acetone, methyl ethyl ketone, cyclohexanone and methyl isobutyl ketone into tetrafluo roethylene/propylene copolymer membranes have been studied using a gra vimetric sorption method at 30, 45 and 60 degrees C. Coefficients of d iffusion have been calculated from Fick's equation. Using these data, the Fick's equation has been solved to calculate the liquid concentrat ion profiles into the membrane materials at different times. The profi les of liquid concentrations have also been calculated using a numeric al scheme based on the finite difference method Activation parameters for diffusion and sorption have been calculated. The experimental and computed results are discussed in terms of the molecular sizes and sha pes of penetrating liquids.