Separation of Heavy Metals Salts from Aqueous Solutions by Reverse Osmosis Membranes (317K-2)

摘要

The aim of this work was the separation of heavy metal salts dissolved in water with coal modified-cellulose acetate (317K-2) heterogeneous RO membranes. Reverse osmosis membranes have been used to study their selectivity properties implying different feed solutions such as aqueous solutions of HgCl2, KMnO4, CrCl3 and CuSO4. The composition of cellulose acetate and powdered coal in ratio (1:1.75 by weight) in casting solvent (acetone) and casting conditions are tested. The powdered coal was modified with 4- nitrobenzene diazonium salt in acetonitrile. Like the cellulose acetate membrane, the cellulose acetate-coal modified membranes separate the trivalent and bivalent ions more than the univalent ions. Regarding the separation of salts solutes with the cations of the same valence, separation increases with the decrease of the cation radius.