Abstract
Malic acid cross-linked poly(vinyl alcohol)/graphene (MA-PVA/Ge) nanocomposite membranes were fabricated by solution-casting method. The effects of PVA, MA, and Ge concentrations on pervaporation (PV) performance of membranes for dehydration of 80 wt% ethanol solution were investigated. The membrane characterisations were performed by atomic force microscopy, transmission electron microscopy, Fourier- transform infrared spectroscopy, X-ray diffraction, tensile testing, differential scanning calorimetry, swelling degree, and water contact angle. The characterisation and PV results indicated that the thermal stability, swelling degree, and separation performance of MA-PVA/Ge nanocomposite membrane were improved compared to neat PVA by adding 10 wt% PVA solution with 20 wt% MA and 0.15 wt% Ge in respect to the weight of PVA (20MA-10PVA/0.15Ge). This membrane exhibited good PV performance with a good selectivityof 596, an equivalent permeate flux of 0.12 kg/m2h, and a high PV separation index of 68.4 kg/m2h fordehydration of 80 wt % ethanol concentration in the feed solution (CF) at feed temperature (TF) of 50 °C, feed flow rate of 60 L/h, and vacuum pressure (PV) of -100 kPa.
