Novel thin nanocomposite RO membranes for chlorine resistance

Abstract

Sulfonated poly(arylene ether sulfone) material containing amino groups (aPES) is successfully synthesized using aromatic substitution polymerization. This material was shown to be a novel thin-film composite (TFC) reverse osmosis (RO) membrane material with high chlorine resistance. Graphene oxide (GO) and aminated graphene oxide (aGO) nanoparticles were also prepared. TFC membranes were prepared using an interfacial polymerization (IP) reaction with trimesoyl chloride (TMC) and amine solution, containing synthesized materials, on a polysulfone (PS) ultrafiltration (UF) support membrane. The synthesized aPES and fabricated TFC RO membranes were characterized by nuclear magnetic resonance spectroscopy and scanning electron microscope. Moreover, RO performances, salt rejection, and water flux were measured using cross-flow cell instrument. The chlorine resistance was evaluated using sodium hypochlorite solution. The membrane fabricated with aPES/GO/aGO was compared with the typical polyamide (PA) TFC membrane which was prepared by the IP reaction with TMC and MPDA on a PS support membrane. The aPES/GO/aGO RO membrane had much higher chlorine resistance than PA RO membrane and showed good RO performances, such as water flux (28L/m(2)h) and salt rejection (98%).