High performance polyvinylidene fluoride (PVDF) mixed matrix membrane (MMM) doped by various zeolite imidazolate frameworks

Abstract

Zeolitic imidazolate framework (ZIF-8) in three particle sizes (40, 70 and 100 nm) was prepared through both solvothermal and hydrothermal methods and employed to decorate polyvinylidene fluoride (PVDF). The finger-like macro-voids, sponge-like poly-porous morphology and surface roughness of prepared membranes were characterized by SEM and AFM microscopy. The FTIR spectrum and XPS analysis bear out the chemical component. ZIF-8 has the characteristics of higher porosity and appropriate pore size, which is a condition for improving the permeability and pollution resistance of the modified membrane. Results indicated that different ZIF-8s have different enhancement effects on PVDF MMM. 100 nm ZIF-8 membrane possessed pure water flux (PWF) of 350 L m−2h−1, which was 10 times more than the bare membrane (30 L m−2h−1), and OVA flux recovery ration (FRR%) is 98%. 40 nm ZIF-8 membrane owned BSA FRR% of 98.4%. The 70 nm ZIF-8 showed the best mechanical properties. The dynamic contact angles of UP-Z70 ranged from 104.5° to 62.5° within 180 s. Furthermore, pore size distribution, molecular weight cut-off (MWCO) and porosity were also researched to evaluate the MMM. The dislodge of Reactive Black KN-B, Reactive Red 3BS and Reactive Brilliant Blue KN-R dyes by MMM were studied under different dye concentrations and transmembrane pressures. The membrane can provide selective separation methods for dyes and Reactive Brilliant Blue KN-R up to 99%. Overall, the permeability, hydrophilicy, anti-fouling performance and wastewater treatment of modified membranes were regulated by the ZIF-8 in a steerable blending reaction modification process.

Development of highly permeable and antifouling poly(vinylidene fluoride) hybrid membranes tailored with ZIF‐8 metal–organic frameworks for water treatment

“…The observed peaks are the characteristic pattern of ZIF-8. Zhou et al and Liu et al also reported similar results [32][33][34][35]. As shown in Figure1C-F, the SEM images and EDX of ZIF-8 revealed that the particles are in the nanoscale and appeared with hexagonal shapes.…”

Preparation and characterization of ZIF-8 and ZIF-67 engineered PVDF mixed-matrix membranes: stability enhancement in pervaporation study

“…From Table 3, it is clear that incorporating MOFs into the polymeric membranes increases surface roughness. 35 The surface roughness of the prepared MOF-based PVDF mixed-matrix membranes depends on the water and DMF diffusion rate during the phase inversion process of the membranes. Incorporating hydrophilic MOFs and their derivatives into the polymeric membrane enhances the transfer rate of DMF and water in the water coagulation bath, which increases the roughness of the MOF-based PVDF mixed-matrix membranes.…”

ZIF-8 modified poly (m-phenylene isophthalamide) (PMIA) hybrid membrane for dye wastewater treatment

“…30,31 Dai et al 32 prepared polyphenylsulfone (PPSU)/ZIF-8 resin microspheres (RMs) membranes for solvent-resistant nanofiltration via NIPS method. Liu et al 33 prepared polyvinylidene fluoride (PVDF)/ZIF-8 mixed matrix membrane with different particle size for dye separation via NIPS method. Sun et al 34 prepared polysulfone (PSf) UF membrane with hydrophilic hollow ZIF-8 (hZIF-8) as the functional additive.…”