Simultaneous spray self-assembly of highly loaded ZIF-8-PDMS nanohybrid membranes exhibiting exceptionally high biobutanol-permselective pervaporation

Abstract

The ability to obtain a maximum loading of inorganic nanoparticles while maintaining uniform dispersion in the polymer is the key to the fabrication of mixed-matrix membranes with high pervaporation performance in bioalcohol recovery from aqueous solution. Herein, we report the simultaneous spray self-assembly of a zeolitic imidazolate framework (ZIF)-polymer suspension and a cross-linker/catalyst solution as a method for the fabrication of a well-dispersed ZIF-8-PDMS nanohybrid membrane with an extremely high loading. The ZIF-8-PDMS membrane showed excellent biobutanol-permselective pervaporation performance. When the ZIF-8 loading was increased to 40 wt%, the total flux and separation factor could reach 4846.2 gm-2h-1 and 81.6, respectively, in the recovery of n-butanol from 1.0 wt% aqueous solution (80°]C). This new method is expected to have serious implications for the preparation of defect-free mixed-matrix membranes for many applications. Thin and functional: A ZIF-8/polymer suspension and a cross-linker/catalyst solution were simultaneously sprayed onto a polysulfone substrate (see picture). The nanoparticles of the zeolitic imidazolate framework ZIF-8 were dispersed uniformly and separated from one another by the polymer chains. The resulting ZIF-8/polymer nanohybrid membranes exhibited excellent biobutanol-permselective pervaporation. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.