Preparation and characterization of new membranes PSU / PVP for the extraction of cadmium ions from acidic solutions

In this work, we developed asymmetric membranes at the base of the PSU / PVP by the phase inversion method and we used Cholic acid (CA) as a carrier, we realized the facilitated transport of cadmium ions in acidic solutions. Macroscopic parameters, permeability P and initial flux J0 related to facilitated transport of these ions were determined, for understanding this process; we have characterized these membranes by various techniques (SEM, angle contact.). To explain this phenomenon of facilitated transport and therefore extraction of these ions in this type of membranes, a mechanism based on the complexation of these ions by the carrier and diffusion of the formed complex through the organic phase has been developed. The experimental results verify this mechanism and we can find the optimum quantity of carrier and determine the microscopic parameters: the association constant Kass and apparent diffusion coefficient D* related to the migration of the complex (Substrate-Carrier) formed through the membrane phase