Intensification of water/ethanol separation by PVA hybrid membrane with different functional ligand UiO-66-X nanochannels in pervaporation process

In order to investigate the effects of MOFs by altering ligands with various functional groups on separation selection in pervaporation dehydration, three hydrophilic UiO-66-X nanoparticles were respectively synthesized and blended into poly (vinyl alcohol) matrix to fabricate water-selective membrane for ethanol dehydration via PV technology. Both the experimental and molecular simulation results confirmed the UiO-66-X counterbalancing factors of enhanced polarity and suitable pore size gave rise to the optimal performance in ethanol dehydration. The PV performances could be tuned by the type and quantity of functional groups carried by UiO-66-X nanoparticles. As a result, the pore aperture of UiO-66-(COOH) 2 nanoparticles provided continuous channel for water diffusion, and water molecules could also be activated attributed to the strong interaction between the UiO-66-(COOH) 2 nanoparticles and water molecules which enhanced the penetration and diffusion of water molecular in hybrid membrane to increase the water flux. The optimized hybrid membranes with UiO-66-(COOH) 2 loading of 8 wt% exhibited the total flux of 979 ± 7 g/(m 2 ·h) and a separation factor of 2084 ± 21.