Poly(vinyl alcohol)-Modified Membranes by Ti₃C₂T_<i>x</i> for Ethanol Dehydration via Pervaporation

Abstract

In this paper, PVA/Ti₃C₂T _<i>x</i> mixed matrix membranes (MMMs) were prepared by mixing the synthesized Ti₃C₂T _<i>x</i> with the PVA matrix, and the pervaporation (PV) performance of the ethanol-water binary system was tested. The morphology, structural properties, and surface characteristics of the membranes were investigated by scanning electron microscopy, atomic force microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, degree of swelling, and water contact angle. The PVA/Ti₃C₂T _<i>x</i> MMMs exhibit excellent compatibility and swelling resistance. Moreover the effects of the Ti₃C₂T _<i>x</i> filling level, feed concentration, and operating temperature on the ethanol dehydration performance were systematically studied. The results demonstrated that the separation factor of PVA/Ti₃C₂T _<i>x</i> MMMs was significantly increased because of Ti₃C₂T _<i>x</i> promoting the cross-linking density of the membrane. Specifically, the membrane showed the best PV performance when Ti₃C₂T _<i>x</i> loading was 3.0 wt %, achieving a separation factor of 2585 and a suitable total flux of 0.074 kg/m² h for separating 93 wt % ethanol solution at 37 °C.