The improvement of antibiofouling properties of a reverse osmosis membrane by oxidized CNTs

Polyamide reverse osmosis (RO) membranes with deposited carbon nanotubes (CNTs) coated with poly(vinyl alcohol) (PVA) on the surface were prepared by interfacial polymerization followed by the deposition of oxidized CNTs and the coating of PVA on the surface. The polyamide membrane with the oxidized CNTs and PVA coating (PA–CNT–PVA membrane) showed much improved mechanical properties and durability compared with the polyamide membrane without CNTs (PA membrane). The PA–CNT–PVA membrane also exhibited much better antifouling properties than the PA membrane and the commercial RO membrane (LFC-1). The improved durability and antibiofouling performances of the PA–CNT–PVA membrane were possible when the CNTs were well-dispersed on the top of the polyamide active layers and stabilized by the thin crosslinked PVA coatings.