Cadmium salts transport through a nanofiltration membrane: Experimental results and model predictions

This article discusses the transport mechanism of cadmium salts (CdCl2, Cd(NO3)2) through a nanofiltration membrane. A model based on the extended Nernst-Planck and the film theory equations is reported. This model is characterized by three transport parameters: the water permeability Lp the ion transmittance Φ and the effective transfer coefficient Keff. The knowledge of the feed and permeate concentrations and the permeate flux enable the calculation of these parameters. The model was used to predict cadmium salt solution rejection by a NANOMAX 50 membrane. The experimental values and calculated predictions are in good agreement.