NaA Nano zeolite incorporated polystyrene mixed matrix membrane for separation of hydrazine and water using pervaporation

Abstract

The composite polystyrene (PS) membranes were prepared in toluene solvent system for pervaporation of hydrazine/water mixtures. Hydrophilic NaA zeolite was incorporated to the extent of 10 - 40% of polymer weight to enhance separation properties. The nanofillers were incorporated into the polymer to reduce degree of swelling and improve selective nature with respect to water. Sorption studies were carried out in water, hydrazine hydrate binary mixture of varying compositions to establish membrane–liquid interactions. Membranes were characterized by FTIR, XRD and SEM to study formationof functional groups and intermolecular interactions, degree of crystallinity and d-spacing, besides surface morphologies of the composite films, respectively. Effect of feed composition, temperature, membrane thickness and downstream pressure on the membrane performance was evaluated using the optimum 40% zeolite-loaded membrane. For a feed mixture containing 36wt% water, a selectivity of 124.89 at a reasonable flux of 32.45 g/m2h was observed. PS membrane appears to have considerable potential to dewater highly alkaline solvents owing to its ability to separate hydrazine hydrate. The composite nature of the membrane makes it feasible to fabricate modular configurations for scale-up.