Hyperfiltration in charged membranes. Prediction of salt rejection from equilibrium measurements

Ion distribution between polybase-collodion membranes and aqueous salt solutions was measured and could be described by an effective charge density, following the association model for polyelectrolyte solutions. The osmotic factor, φ_p, derived from these measurements is close, but not equal, to that measured in the corresponding polybase solutions. The effective charge density resulting from the equilibrium measurements was introduced into the equation for salt rejection, derived previously for the TMS model. Satisfactory agreement with measured rejections was found.