Facile preparation of homogeneous polyelectrolyte complex membranes for separation of methanol/methyl tert-butyl ether mixtures

Facile preparation of homogeneous polyelectrolyte complex membranes (PECMs) based on sulfonated polyarylethersulfone with cardo (SPES-C) and polyethyleneimine (PEI) is reported in this work. The PECMs were characterized using Fourier transform infrared (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and contact angle metering. The FTIR results confirmed the acid–base crosslinking between SPES-C and PEI. With increasing PEI content, both the hydrophilicity and the amorphous region of the PECMs increased. The effect of PEI content on the degree of swelling and separation performance of the PECMs was investigated. PECM-16 was found to have the optimum performance. A flux of 0.194 kg m−2 h−1 and a separation factor of 1860 at 40 °C were achieved in pervaporation of 15 wt% methanol/methyl tert-butyl ether mixture.