چكيده به لاتين
In this study, charcoal-based carbon nanomaterial (CNM) was used to modify the thin film composite (TFC) membrane for forward osmosis (FO) process. For this purpose, different amounts of CNM (0, 0.3, 0.5, 0.7, and 1 wt.%) were incorporated into polyethersulfone (PES) and the effect of CNM addition on hydrophilicity, morphology, and surface roughness of the prepared membrane substrates were investigated. It was observed that by addition of the optimal amount of CNM (0.5wt.%, MS-2), structure of the substrate is more significantly improved compared to the unmodified substrate (MS-0). In order to fabricate the TFC-FO membranes, m-phenylenediamine (MPD) was used as aqueous phase and trimesoyl chloride (TMC) was used as organic phase for formation of polyamide (PA) layer on the substrate surface. FO performance of the prepared TFC membranes was evaluated in both FO mode (active layer faced to feed solution) and PRO mode (active layer faced to draw solution) using DI water as feed solution (FS) and 1 M NaCl solution as draw solution (DS). Also, in order to study the capability of TFC membranes for desalination purposes, the Caspian Seawater was used as FS. It was found that incorporation of CNM into the TFC membrane substrate leads to the reduced structural parameter (S) which mitigates the effect of internal concentration polarization (ICP). The obtained results indicated that water flux in both FO and PRO mode for the MS-2 membrane is approximately 3 times higher than that for the neat membrane and reverse salt flux is slightly reduced. According to the results, amount of Js/Jw value significantly decreases from 1.40 to 0.25 g/L. Therefore, this work demonstrates that charcoal-based CNM is a suitable candidate for modification of TFC-FO membranes to achieve high water flux as well as high membrane selectivity.
