Removal of Cu2+ and Ni2+ from wastewater by reverse osmosis processes and chelating agent

The performance of a thin film composite spiral wound type membrane in reverse osmosis process is studied for rejecting the and from single-salt and mixed-salt systems. The experimental results for the systems including sulfate salts, indicated that removed from the sample solutions was more than , however for both ions the salts concentration had a decreasing effect on ions removal. Also the ion rejection in the different operating pressure was calculated and reported. The obtained results indicated that the ion rejection depends on hydraulic and osmosis pressures, however, by considering the operation limitations the ion rejection factor is less than the unit. To examine the effect of size of the ions on the rejection by the membrane, the ions and were chelated by disoduim salt ethylene diamine tetraacetic acid (Na2EDTA) as a chelating agent. The obtained results indicate that Na2EDTA can increase the rejection efficiency of the membrane used in the process of and removal from industrial wastewater.

Keywords:

Industrial wastewater , reverse osmosis , chelating agent , heavy metal , rejection