Metal-organic framework/zeolite nanocrystal/polyvinylidene fluoride composite ultrafiltration membranes with flux/antifouling advantages

Abstract

In this study, hydrophilic zirconium 1,4-dicarboxybenzene (UiO-66) and chromium (III) terephthalate (MIL-101) metal-organic frameworks (MOFs) and faujasite (FAU) zeolite nanocrystals were synthesized successfully and incorporated into polyvinylidene fluoride (PVDF) matrix as nanofillers to fabricate mixed matrix membranes (MMMs) via non-solvent induced phase separation (NIPS) process. The effects of casting solution temperature and casting speed as two important factors in membrane fabrication via phase inversion method on performance and structure of the neat PVDF membrane were investigated. Then, various contents of the synthesized nanofillers were loaded into the PVDF matrix and the effects of the synthesized nanofillers on hydrophilicity, pure water flux (PWF), morphology and antifouling properties of the fabricated MMMs were explored. Antifouling studies were also performed using Bovine serum albumin (BSA). The obtained results demonstrated that incorporation of the synthesized nanofillers into the PVDF membrane has positive effect on performance and structure of the fabricated MMMs and the MMM containing 0.1 wt% MIL-101 showed the best performance with water flux of 360 LMH, BSA rejection of 100%, irreversible fouling of 22.2% and flux recovery ratio of 77.7%. This work highlighted the potential application of the MOFs as effective nanofillers for MMM fabrication.