CONCENTRATION AND SEPARATION OF AQUEOUS-SOLUTIONS OF CU2+, NI2+, FE3+BY DEXTRAN

The effects of water-soluble polymers on the concentration and separat ion of the aqueous solutions of the metal ions have been studied. The separation of metal ions can be possible by ultrafiltration-complexati on process. The effect of Dextran, which is a water-soluble polymer, o n the concentration and separation of metal ions (Cu2+, Ni2+, Fe3+) ha ve been investigated by using EC-PEG 4000 alloy membranes. The permeab ility of these membranes for metal ions has been recorded at constant pressure but different pH values. It has been noticed that the highest water-permeable membrane is also permeable towards Cu2+ and Ni2+ I bu t has shown a considerable retention for Fe3+ as a result of the hydro lysis of Fe3+ The retentions of metallic ions and metallic-ion-Dextran couples have been determined at constant pressure but different pH an d polymer concentration values. It has been shown that Fe3+/Ni2+ and F e3+/Cu2+ couples can be separated by using Dextran. (C) 1995 John Wile y and Sons, Inc.