An Experimental Investigation: Effect of Phase Inversion Methods on Membrane Structure and Its Performance on PEG Filtration

In this work, the effect of different phase inversion process on membrane morphology and performance was studied. Polyethersulfone (PES) based polymeric membranes was fabricated containing polyvinylpyrrolidone (PVP) and carboxylic functionalized multiwall carbon nanotubes (MWCNT) as additives and polyethylene glycol (PEG) having a molecular weight 1K, 10K and 35K (Dalton) were used as a model solution for observing the rejection/filteration ability of fabricated membranes. Non-solvent induce phase separation (NIP) and dry-wet phase separation (DWP) method was adopted for membrane synthesis. The FTIR spectra showed that PVP/MWCNT was effectively blended with PES polymer and different phase inversion method led to different internal morphologies of membranes as confirmed by FESEM images. The PEG rejection results suggested that membranes formed by DWP method had approximately double rejection ability than membranes formed by NIP process.