Tubular PAN/CNC thin film nanocomposite (TFN) pressure retarded osmosis (PRO) membrane: fabrication and preliminary evaluation in desalination process

Abstract

Abstract The aim of this work is to fabricate tubular nanocellulose-based nanofiber pressure retarded osmosis (PRO) by electrospinning. The PRO process requires high performance, high flux, high rejection and resistant membranes under harsh conditions. Because conventional phase-inversion membranes are not sufficient to perform the required water flux. Because of this reason, alternative membrane fabrication methods need to be develop. Recently, lots of studies are carried out to fabricate strong enough nanofiber pressure retarded osmosis membranes which are resistant higher pressure pressure while providing high flux and high rejection rates. In this study, cellulose nanocrystal (CNC) added PAN nanocomposite nanofiber PRO membranes successfully fabricated by tailor made electrospinning equipment. According to the Scanning Electron Microscopy (SEM), FT-IR, Dynamic Mechanical Analysis, Porometer and Contact Angle analysis results, it is concluded that PAN and CNC provided a complete mixture and the addition of CNC increased the mechanical strength in the PAN membranes which is the crucial phenomena in PRO applications.In this study, the newly fabricated membrane achieves a higher PRO water flux of 405.38 LMH with using a 1 M NaCl and a DI as feed water. The corresponding salt flux is found as 2.10 gMH which is higher than our previous study (Pasaoglu et al., 2020). The selectivity of the reversed flux represented by the ratio of the water flow to the reversed salt flux (Jw/ Js) was able to be kept as high as 193.03 L/g for PRO operation.As far as we know, the performance of the work developed membrane in this study has shawn better performance than all PRO membranes reported in the literature previously.