Efficacy of carbon nanotube positioning in the polyethersulfone support layer on the performance of thin-film composite membrane for desalination

Abstract

A thin-film composite (TFC) membrane with a functionalized carbon nanotubes (fCNT) blended support layer (fTFC) was successfully synthesized by phase inversion method and interfacial polymerization. fTFC membrane was characterized and compared with TFC bare membrane to investigate the effect of fCNT on membrane performance. The fTFC membrane showed enhanced water permeability due to its increased hydrophilicity, enhanced pore properties of the support layer without sacrificing NaCl rejection compared to that of the TFC bare membrane. The fTFC membrane showed a 10-20% enhanced water flux in the seawater reverse osmosis (SWRO) at pressures over 50 bar, and a 90% enhanced water flux in the brackish water reverse osmosis (BWRO) operating pressure at 30-40 bar. Moreover, the fTFC membrane exhibits higher organic fouling resistance compared to the TFC bare membrane due to the 50% higher initial water flux and more negative surface charged surface. (C) 2015 Elsevier B.V. All rights reserved.