Preparation of poly(vinyl alcohol) - chitosan blended membranes and their applications in pervaporation separation of water/isopropanol and methanol/benzene mixtures

Poly (vinyl alcohol) (PVA) and chitosan (CS) are widely used as membrane materials. Here PVA/CS blended membranes were prepared over a range of 0–100 wt% CS loading by solution casting method and crosslinked with glutaraldehyde (GA). The prepared membranes were applied to separate water/isopropanol mixture by pervaporation. They were also characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). As the CS loading increases, total flux greatly increases whereas selectivity reaches a maximum at around 80 wt% CS. At 25 °C, for 85 wt% isopropanol in the feed mixture, the crosslinked blend membrane with 80 wt% CS shows the total flux of 8623 kg μm m-2 h-1 and best selectivity of 266223. This membrane also showed very excellent performance for methanol/benzene separation at different methanol feed compositions. At 5 wt.% methanol in feed mixture, at 25 °C, the highest selectivity value of 312.4 with 4.52 kg μm m-2 h-1 of flux was obtained.

کلیدواژه ها:

polyvinyl alcohol ، chitosan ، polymer blending ، pervaporation