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[Display omitted] • –OH and Ag-functionalized nanosized FAU-Ag-OH zeolite was successfully synthesized. • TFN membrane with bifunctionalized FAU-Ag-OH zeolites as nanofiller was prepared. • The doping of FAU-Ag-OH zeolite resulted in a thinner PA layer with stripe morphology. • The M–0.05 membrane achieved an antibacterial efficiency of 95.4% and a FRR of 85%. • The water permeance of M–0.05 membrane with FAU-Ag-OH increased by 128%. Poor water permeance and biofouling significantly limit the application of nanofiltration (NF) membranes in wastewater treatment and seawater desalination. Herein, bifunctionalized FAU-Ag-OH zeolites, featuring abundant hydroxyl groups and silver ions on their surface, were designed and incorporated into polyamide (PA) layer of a thin-film nanocomposite (TFN) membrane, effectively enhancing the antibiofouling properties and water permeance of membrane. The plentiful hydroxyl groups and well-dispersed silver ions on the bifunctionalized FAU-Ag-OH zeolites impart the membrane with more negative surface charge, increased hydrophilicity, and superior antibiofouling property. Additionally, the doped FAU-Ag-OH zeolites can retard the diffusion of piperazine during interfacial polymerization (IP) process and have improved chemical compatibility with polymers, which results in desirable membrane structure. Consequently, the optimal M–0.05 membrane containing FAU-Ag-OH zeolites exhibited a 2.3-fold increase in water permeance (18.8 ± 2.0 L m−2 h−1 bar−1) and enhanced antibiofouling ability (with antibacterial efficiency up to 95.4 % and flux recovery ratio up to 85 %) compared with the TFC membrane. The successful fabrication of such membrane with enhanced antibiofouling properties and improved water permeance is expected to promote the application of NF membranes in water treatment. [ABSTRACT FROM AUTHOR]

• Inclusion as an efficient purification method was demonstrated with 2-HP-γ-CDP 1:5. • 2-HP-γ-CDP was first synthesized by using 2-HP-γ-CD and TFTPN. • The removal rate of 4,6-DMDBT or MB using 2-HP-γ-CDP 1:5 was 15 times that of AC. • The q m of 2-HP-γ-CDP 1:5 towards 4,6-DMDBT or MB was higher than reported materials. • Removal was realized by inclusion of the size-matched molecules in CD units. For specific removal of tricyclic organic sulfur/nitrogen pollutants in fuel and effluent, inclusion not adsorption as an efficient purification method was studied with cyclodextrin polymers. Herein, a novel 2-hydroxypropyl- γ -cyclodextrin polymer (2-HP- γ -CDP) was synthesized using tetrafluoroterephthalonitrile (TFTPN) as cross-linker for specific removal of tricyclic organic sulfur/nitrogen pollutants, including 4,6-dimethyldibenzothiophene (4,6-DMDBT) in fuel and methylene blue (MB) in effluent. When the molar ratio of 2-HP- γ -CD and TFTPN was 1:5 in the synthesis process, the prepared micro-mesoporous 2-HP- γ -CDP 1:5 with a surface area of 365.4 m2·g−1 has the best removal performance. 2-HP- γ -CDP 1:5 was almost 15 times the commercial activated carbon in removal rate. Meanwhile, the maximum removal capacity of 2-HP- γ -CDP 1:5 was higher than that of most reported traditional adsorbents. Furthermore, 2-HP- γ -CDP 1:5 was easily regenerated with ethanol and almost unchanged in capacity over 5 cycles. It was demonstrated that most of size-matched 4,6-DMDBT and MB removed by 2-HP- γ -CDP 1:5 enter the hydrophobic inner cavity of 2-HP- γ -CD units. The pleasant inclusion removal method offers the potential applications of 2-HP- γ -CDPs in fuel desulfurization and effluent purification. [ABSTRACT FROM AUTHOR]

The preparation of MOF composite membranes with the interfacial polymerization method and the functional modification with PEI to enhance Li+/Mg2+ sieving properties. [Display omitted] • MOF "monomers" are constructed into membranes via interfacial polymerization. • The surface charge and pore size are regulated by PEI post-modification. • The high MOF ratio provides more transport channels for ions. Advanced ion transportation channels aided by charge and suitable aperture play a crucial role in achieving precise separation of ions. Here, we report a MOF composite membrane with electropositive surface and sub-nanometer-sized ion transport channels for efficient Li+/Mg2+ separation. The membranes were fabricated using MOF "porous monomers" and trimesoyl chloride (TMC) through interfacial polymerization, and subsequently modified with amino-functionalized polyethyleneimine (PEI). The abundant porosity of the MOFs composite membrane includes the inner and the intergranular pores of MOF provided a rapid transport channel for Li+ ions, and a superior Li+ permeation rate of 0.68 mol m−2h−1 (a 10 times enhancement compared to the currently leading MOF membranes). Moreover, the improved positively charged surface (from −78 mV to + 4 mV at pH = 7) and reduced mean pore diameter (from 1.13 nm to 0.8 nm) of the membrane caused a remarkable selectivity of 13.2 for Li+/Mg2+. The design concept of the above MOFs based membrane provides a novel approach for developing high-quality MOF composite membranes for improving Li+/Mg2+ separation performance. [ABSTRACT FROM AUTHOR]