Mixed matrix membranes (MMMs) of hydroxyl propyl cellulose/ Poly(vinyl alcohol) (HPC/PVA) blends loaded with 5, 10, 15 wt% of phosphotungsticacid (PWA) and cross linked with gluteraldehyde have been prepared by the solution casting technique. The membranes were characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction study (XRD) to confirm cross linking and assess the intermolecular interactions. Thermal stability and crystallinity were determined from thermo gravimetric analysis (TGA) and differential scanning calorimetry (DSC) studies. The morphology of membranes was characterized by SEM studies, which indicates good compatibility of these membranes. Sorption studies were carried out to evaluate the extent of interaction and degree of swelling of the membranes, in pure liquids as well as mixtures of water and ethanol. Pervaporation (PV) experiments have been performed at 30 °C to separate water - ethanol feed mixtures containing 10-17.5 wt% of water. The pervaporation performance was evaluated by varying experimental parameters such as feed composition, different polymer compositions and found to be potential membranes for separation of water-ethanol mixtures. The results reveal that the MMMs of HPC-PVA (M2) containing 10 wt% of PWA showed the flux is of the order of 0.3948 kgm-1h-1 and selectivity of the order of 1789 at 10 wt% water feed. From this it is concluded that the present blend membrane is a promising candidate for dehydration of aqueous ethanol. Flux of the blend membranes decrease with increasing concentrations of PWA. However, a significant improvement in PV performance was observed for PWA- loaded mixed matrix membranes (MMMs) compared to the pristine HPC/PVA blend membrane.

Keywords:  Pervaporation; Hydroxypropyl Cellulose; Poly(vinyl alcohol) Blends; Phosphotungstic Acid; Water - Ethanol Mixture;