Fabrication of Nano-Composite Membrane for FO Desalination

Abstract

The aim of this work is to solve the current issues experienced in forward osmosis (FO) membranes such as low water flux, membrane fouling, and high reverse solute flux (RSF). We also propose a novel technique to eradicate the problems faced with electrospinning technique for the fabrication of nanofibers (NFB). Polysulfone (PSF) and polyethersulfone (PES) are used to fabricate highly porous FO NFB membrane with enhanced water flux and minimal RSF value. In this study, NFB are produced by a novel solution blow spinning (SBS) technique. These fabricated NFB are tested for the FO process and further modified by interfacial polymerization (IP) technique to deposit polyamide (PA) layer incorporating nanomaterial (graphene oxide) The structure and morphology of the NFB are characterized using (SEM), (AFM), Contact angle measurement, (FTIR) and (XRD) studies. These techniques confirmed the changes in the membrane morphology, formation of PA layer and presence of graphene oxide (GO) in it. The novelty of this work is the use of solution blown spinning technique for the NFB membrane production, which has not been reported for use in membrane-based desalination. NFB formed using this technique showed considerable enhancement in water flux and decreased RSF. In addition, the prepared NFB membrane after the heat pressing post treatment exhibited good mechanical strength with an improvement in young's modulus almost three to four times. The FO performance of the nanofiber membrane showed a significant increase in flux of almost two-fold, while having minimal RSF values below 0.2 g/m2h