A contribution to the translation of retention curves into pore size distributions for sieving membranes

The analysis of solute and solvent transport through capillaries according to sieving and Poiseuille flow models allows the calculation of retention curves corresponding to a given pore size distribution. A log-normal distribution is assumed with the average radius and the geometric standard deviation as parameters. A method is described to retrieve the parameters of the apparent pore size distribution of a clean or a fouled membrane when rejection measurements are available for test molecules. The method is applied to experimental data obtained with dextran filtered on polysulfone membranes. The curves calculated using the parameters given by the method are in good agreement with experimental data.