REMOVAL OF HEAVY METALS USING REVERSE OSMOSIS

Abstract

The aim of this work is to study reverse osmosis characteristics for copper sulfate hexahydrate(CuSO4.6H2O), nickel sulfate hexahydrate (NiSO4.6H2O) and zinc sulfate hexahydrate (ZnSO4.6H2O)removal from aqueous solution which discharge from some Iraqi factories such as Alnasser Company formechanical industries. The mode of operation of reverse osmosis was permeate is removed and theconcentrate of metals solution is recycled back to the feed vessel. Spiral-wound membrane is thin filmcomposite membrane (TFC) was used to conduct this study on reverse osmosis. The variables studied aremetals concentrations (50 – 150 ppm) and time (15 – 90 min). It was found that increasing the time results in an increase in concentration of metal in permeate, feed concentration in feed vessel and recovery percent. While, it was found that water flux, rejection percent and mass transfer coefficient is decreasing with increasing operating time. Also, it was found that the permeate concentration and feed concentration in feed vessel increases with increasing feed concentration, on the contrary, water flux, the percentage of recovery, rejection percent and mass transfer coefficient decreases with increasing the concentration of feed solution. The maximum rejection of copper, nickel, and zinc salts are 96.6%, 95.7% and 98.2% respectively. The maximum recovery percentage of copper, nickel, and zinc salts are 40.8%, 41.35% and 38.44% respectively. The pure water permeability constant was calculated for TFC membrane.