“…Electrostatic repulsion and attraction are usually used in NF process to explain the phenomenon of flux decline and fouling (Bacchin et al, 2006;Childress and Elimelech, 2000;Bellona and Drewes, 2005;Peng et al, 2004). The ion retention through NF membrane could be classified into two main categories (Peeters et al, 1998):…”