Recovery of metals by Donnan dialysis with ion exchange textiles

Abstract Donnan Dialysis is an adequate process to recover metals from dilute solutions, however, when the enrichment is needed, the osmosis phenomenon occurs and reduces the efficiency of the operation. Moreover, a lot of ion exchange membranes are so far from the ideal permselectivity. In this work, the combination of ion exchange membranes with an ion exchange textile is used to perform separation — concentration of copper and silver by means of an unconventional Donnan dialysis. The results obtained have shown a great reducing of the osmosis phenomenon and a good yield for the concentration of the metallic ions. Hypotheses about the transfer mechanism through the system composed by ion exchange membranes and the ion exchange textile are emitted. A correlation between the ion hydration and their ability to cross through the proposed system is established.