Figoli et al. (2010) studied the removal of pentavalent arsenic from synthetic water by two commercial NF membrane (NF90 and N30F). They found that an increase of pH and a decrease of operating temperature and As feed concentration led to higher As removal for both membranes. Among the parameters affecting the As rejection, feed concentration plays a key role for the production of a permeate stream. In recent years, Murthy and Chaudhari devoted a lot in the removal of heavy metal ions using NF membrane. They reported the application of a thin-film composite polyamide NF membrane for the rejection of nickel ions from aqueous wastewater (Murthy and Chaudhari, 2008). The maximum observed rejection of nickel is found to be 98% and 92% for an initial feed concentration of 5 and 250 mg/L, respectively. And they investigated the binary heavy metals (cadmium and nickel) separation capability of a commercial NF membrane from aqueous solutions (Murthy and Chaudhari, 2009). The maximum observed solute rejection of nickel and cadmium ions is 98.94% and 82.69%, respectively, for an initial feed concentration of 5 mg/L.