Polyvinyl Alcohol/Agarose Blended Membranes for Pervaporative Separation of Ethanol/Water Mixture

Alcohol dehydration is accomplished by various processes, especially pervaporation with increased attention and applications. Many hydrophilic polymeric membranes have been prepared and used for alcohol dehydration. Polyvinyl alcohol (PVA) is one of the most important polymeric membranes in this regard. In this study, modification of the prepared polyvinyl alcohol membranes by blending method them with Agarose (Aga) in order to achieve higher separation performance is studied. PVA/Aga blended membranes are prepared and used for separation of ethanol/water solution using pervaporation process. The structure of the membranes was investigated using SEM and contact angle tests. In the carried out experiments, pervaporation operating temperature and pressure are kept fixed at 30 °C and - 830 mbar abs, respectively, and effects of the feed composition and the blending ratio on the membrane separation parameters are studied. The results showed that membranes have enhanced separation performance for water/ethanol mixtures. The highest selectivity as infinity and flux of 0.243 kg/m2h was obtained for the 50 wt. % Aga membrane and the feed mixture of 30 wt. %. The 60 wt. % Aga membrane selectivity and flux for dehydration of the feed mixture containing 70 wt. % ethanol are obtained as infinity and 0.838kg/m2h, respectively.