| Popis: |
The partition and diffusion coefficients of aqueous solutions of aromatic compounds through a thin, dense cellulose acetate membrane were measured at 20°C. The water content and the thickness of the prepared membranes varied from 0.121 to 0.610 by volume fraction and from 17 to 88 μm, respectively. The aromatic solutes used were phenol, aniline, hydroquinone and p -chlorophenol. The solute concentration ranged between 9.0 x 10 -5 and 1.0 x 10 -3 mol/l. The partition coefficients had the following order: p -chlorophenol, phenol, aniline, hydroquinone; they were experimentally correlated with the water content of the swollen membranes. The dependence of the diffusion coefficients on the water content of the membrane was examined using as basis a pore model and a free volume model, respectively. The diffusion coefficients were adequately correlated with the water content of the membrane according to the relation given by the free volume model. |
