Development and Characterization of Silicotungstic Acid-loaded Sodium Polymeric Composite Membranes for Pervaporation Applications

Efforts have been focused on the membrane synthesis, specifically enhancing membrane properties through the incorporation of zeolites into a polymer matrix. This study emphasizes the development of sodium carboxymethyl cellulose (NaCMC)/poly(vinylpyrrolidone-co-vinyl acetate) [P(Vp-co-VAc)] matrix composite membranes via solution casting method, incorporating varying amounts of silicotungstic acid (STA) (5, 10, and 15 wt.%) for the pervaporation dehydration of a water-isopropanol mixture. The developed films were characterized by FTIR, DSC, TGA, XRD and SEM techniques. Among all the STA-loaded membranes, the optimum pervaporation performance was observed in the MSTA15 membrane, which had a flux equal to 0.533 kg/m2 h at 35 ºC and a separation factor of 118.52 for a 40 wt.% water-isopropanol feed composition. The developed membrane exhibits a good hydrophilic nature and a molecular sieve effect. Furthermore, STA-loaded membranes showed the improved pervaporation performance compared to pristine membranes. These results of this study suggested that the STA-loaded composite membranes act as prominent materials for the effective dehydration of isopropanol.