The permeability–selectivity trade‐off of membrane is a major challenge limiting the development of pervaporation (PV) technology. Rational design of high‐performance mixed matrix membranes (MMMs) has the potential to break off the trade‐off. Herein, a solvent‐assisted linker exchange‐based strategy is reported to introduce fluoroalkyl into metal–organic framework‐808 (MOF‐808). The pore size of fluorinated MOF‐808 can be adjusted with fluoroalkyl of different chain length (like trifluoromethyl and pentafluoropropyl). Then, the fluorinated MOF‐808/polyether block amide (PEBA) MMMs are prepared for the PV of n‐butanol/water. Compared with pristine PEBA membrane, 20 wt% 3F‐MOF‐808(P)/PEBA MMMs (3F = ‐CF₃ group; P = postmodification method) exhibit 69% increase in permeation flux and 33% increase in separation factor in the PV of 2.5 wt% n‐butanol aqueous solutions at 70 °C. Based on Grand Canonical Monte Carlo and molecular dynamics simulations, fluorinated MOF‐808 shows better butanol affinity (pull effect) and stronger water repulsion ability (push effect). And the “push–pull effect” between fluorinated MOF‐808 with butanol/water is helpful to enhance the PV performance of MMMs. The application of “push–pull effect” provides a new strategy for the rational design of high‐performance MMMs, which is of great significance for the in‐depth research and application of PV technology.

The compatibility of poly (vinylidene fluoride) (PVDF) and polyurethane (PU) was studied based on the theoretical analysis of solubility parameter and mixing enthalpy. The results showed that PVDF and PU are partially compatible. Then, the blend membranes of PVDF–PU with 5, 10, and 80 wt.% PVDF content were prepared with the application of solution blending in solvent N, N-dimethylacetamide (DMA). The membranes were characterized by Fourier transformed infrared spectroscopy (FT-IR) to assess the intermolecular interactions. And the morphology of the membranes was studied by scanning electron microscope (SEM). 80wt.% PVDF–PU membrane was porous. However, 5% and 10% PVDF–PU membrane were suitable for pervaporation. The study showed that the degree of swelling (DS) of PVDF–PU membrane increased with the phenol concentration, which suggested that these membranes have stronger sorption capacity to phenol. Then, the pervapration performance of the membranes was examined. The results showed that the pevaporation performances of the blend membranes have been improved comparing with the plain PU membrane.

Because of the preferential butanol selectivity of some ionic liquids (ILs), an increasing amount of research has appeared regarding their application in butanol separation. In this research, two ionic liquids, namely, 1-ethyl-3-vinylimidazolium bis[(trifluoromethyl)sulfonyl]imide ([EVIM][Tf₂N], IL1) andN-octyl-pyridinium bis[(trifluoromethyl)sulfonyl]imide ([OMPY][Tf₂N], IL2), were applied to modify a mesoporous molecular sieve MCM-41. The IL-modified MCM-41 samples were characterized by XPS, BET, XRD, SEM and TEM. The ionic liquid-modified MCM-41 was incorporated into the polymer PEBA to prepare mixed matrix membranes to study the influences of the filling of IL-modified MCM-41 and operating conditions on the performance of the mixed matrix membrane for butanol pervaporation. The results indicated that the pervaporation performance of the PEBA membrane was enhanced by the incorporation of IL-modified MCM-41. When the temperature of the feeding liquid was 35°C and the mass fraction of butanol was 2.5 wt%, the 5% MCM-41-IL2-PEBA membrane showed a permeation flux of 421.7 g m⁻²h⁻¹and a separation factor of 25.4. The permeation flux and the separation factor of the membrane increased as the temperature of the feeding liquid increased. The results of the long-period experiment suggested that the 5% MCM-41-IL2-PEBA membrane exhibited high stability within 100 h of operation.