Determination of some transport coefficients for the skin and porous layer of a composite membrane

Retention curves, membrane potential, diffusion and electrical resistance for two membranes a composlte membrane (HR 95) and the support membrane (without the skm layer), have been measured for different solutions of NaCl and MgClz Salt permeabllltles m the skm and porous layers of the composite membrane were calculated and these latter values were compared with those obtained mth the porous polysulfone membrane by diffusion expenments From the expenments it was concluded that 92% of the total flux-resistance was due to the selective skm layer, whereas only 78% of the total diffusion resistance under dialysis condltlons was due to the skm layer A compmson of the expenmental and calculated values for the electrical resistance of the polysulfone membrane has also been made In both cases, good agreements were found Cation transport numbers m the skm and porous layers of the composite membrane have also been obtamed