METHODS OF MEASURING DIFFUSION-COEFFICIENTS OF WATER AND POTASSIUM-CHLORIDE IN AQUEOUS-SOLUTION IN CELLULOSE-ACETATE MEMBRANES

An open-ended capillary cell has been developed to measure thermodynam ic diffusion coefficients of electrolytes, in aqueous solution, in swe lled polymeric membranes. Also a new method to determine the integral diffusion coefficient of water in membranes is presented. In this work we present a description of the methods as well as the experimental r esults of the diffusion coefficients of potassium chloride and water i n cellulose acetate (CA) membranes. The results are in good agreement with those described elsewhere which shows the reability of the method s.