Pervaporation separation of dimethyl carbonate/methanol azeotrope through cross-linked PVA-poly(vinyl pyrrolidone)/PAN composite membranes

Pervaporation (PV) separation of dimethyl carbonate/methanol azeotrope was investigated using composite membranes consisting of Poly(vinyl alcohol) (PVA)/poly(vinyl pyrrolidone) (PVP) blend membrane as active layer and a polyacrylonitrile ultrafiltration membrane as substrate. The active layer was physically blended and cross-linked with glutaraldehyde (GA). The chemical and physical properties of the blend membranes with different proportions of PVA/PVP were characterized by Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), X-ray diffraction, thermogravimetric analysis, and contact angle measurement. The PV properties of the membranes were investigated by the separation of azeotrope. The effects of PVP, GA content, and operating temperature on PV performances were investigated. Permeation flux increased with increasing PVP content and feed temperature, while separation factor decreased. However, the separation factor increased with increasing GA content, whereas the flux decreased. The results showed that the membrane containing 70wt% PVP and 0.5wt% GA exhibited excellent PV properties with a flux of 955.77gm(-2)h(-1) and separation factor of 68.00 at 50 degrees C.