Post-synthetic MIL-53(Al)-SO3H incorporated sulfonated polyarylethersulfone with cardo (SPES-C) membranes for separating methanol and methyl tert-butyl ether mixture

The post-synthetic MIL-53(Al)-SO3H was prepared and incorporated into sulfonated polyarylethersulfone with cardo (SPES-C) polymer matrix to form mixed matrix membranes (MMMs). The as-prepared MIL-53(Al)-SO3H was characterized by wide angle X-ray diffraction (WAXRD), fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), intelligent gravimetric analysis (IGA), scanning electron microscope (SEM) and elemental analysis. Positron annihilation lifetime spectroscopy (PALS), thenno gravimetric analysis (TGA), SEM, FTIR and water contact angle measurements were performed to investigate the properties and structure of MMMs. The results showed that MIL-53(Al)-SO3H was successfully synthesized without crystal structure collapse. The particle sizes were in nanometer scale. MIL-53(Al)-SO3H preferentially adsorbed methanol (MeOH) over methyl tert-butyl ether (MTBE). MIL-53(Al)-SO3H dispersed in SPES-C phase uniformly and no obvious interfacial defects could be observed. The membrane hydrophilicity, swelling behavior as well as free volume parameters could be effectively tuned by changing filler loading. The as-prepared MMMs demonstrated excellent separation performance and encouraging long-term stability for MeOH (15 wt%)/MTBE mixture. With increasing the filler loading, the permeation flux increased and the separation factor showed an up and down trend. When MIL-53(Al)-So(3) H loading was below 15 wt%, an antitrade-off phenomenon was obtained. M-15 with 15 wt% loading exhibited the optimal separation performance (permeation flux of 0.368 kgm(-2)h(-1 )and separation factor of 1990).