New membranes with complexing abilities were obtained by grafting titanate coupling agents bearing ethylenediamine groups (EDA, strong chelating ligand towards Cu2+) or pyrophosphate groups (PP, weak chelating ligand towards Cu2+ and Zn2+) on inorganic nanofiltration membranes. The retention of 10 mmol l(-1) chloride solutions of Cu2+ and Zn2+ by the unmodified NF membrane (no complex formation) and the PP grafted membrane (formation of weak complex) was about 50% which is roughly the retention of Ca2+ (no complex formation) with the EDA grafted membrane. Complex formation with the PP grafted membrane does not appear strong enough to enhance Zn2+ and Cu2+ retention. The retention of Cu2+ was enhanced up to 80-90% with the EDA grafted membrane, due to the occurrence of formation of a strong complex with EDA groups. Contrary to resin process where a breakthrough curve is expected, a steady-state of Cu2+ retention was observed, whereas Cu2+ in the feed solution was about 50 times the membrane capacity to bind the metal cation.