View article

To improve the chlorine resistance of the polyamide-based NF membranes, ferric ion and tannic (Fe^III-TA) networks were grafted onto the polyamide membrane surface via an in-situ modification strategy. The separation performance tests by a cross-flow NF system showed that the grafted membrane (TFC-n) possesses an obviously improved rejection for the selected salts, dyes, and micropollutants with only ~10.0% decrease in water permeability. The chlorination experiments under various pH values demonstrated that the TFC-n membrane presents much superior chlorine resistance than that of the control membrane. Importantly, the grafting layer was also applied to a commercial NF 270 membrane, and the Fe^III-TA grafted NF 270 membrane exhibited much higher chlorine resistance than that of the bare NF 270 and polyvinyl alcohol (PVA) coated NF 270 membranes. The greatly enhanced chlorine resistance …