Application of Nanofiltration Technology in Heavy Metals (Ni, Cu and Zn) Removal from Wastewater

One of the main sources of environment pollution is the industrial wastewater which contains heavy metals and can be found in many industries such as plating industry. If these heavy metals enter in the human body, would cause many health problems. The aim of this study was to investigate the possible application of nanofiltration technology in removal of three heavy metals (nickel, zinc, and cupper) as the most representatives of heavy metals in plating effluents. The effects of different pressure, concentration, and time of filtration on removal of these elements were evaluated. Two concentrations levels of heavy metals (25 and 50 mg/L) were studied under three different pressures of 4, 6 and 8 bar. pH and temperature were considered constant in all experiments. The results showed that increasing of pressure resulted in increased in removal. This was more significant for Cu (100% removal) than Zn and Ni under 8 bar of pressure. Also, it was found increasing of concentration resulted in decreased removal of heavy metals. The results showed that Zn removal decreased from 99% in 25 mg/L to 97. 07% in 50 mg/L. Finally, the filtration time caused a positive effect in the heavy metals removal