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Loose nanofiltration membranes (LNMs) have attracted increasing attention due to their applications in sustainable management of high salinity textile wastewater. Remained challenges include achieving efficient dye/salt fractionation and mitigating high biofouling tendencies. In this work, Ag-loaded UiO-66-NH2(Ag@UiO-66-NH2) nanoparticles were prepared by a simple method of stirring, and subsequently used to blend with cellulose acetoacetate (CAA) to obtain antibacterial Ag@UiO-66-NH2@CAA (MOF@CAA) LNMs. Water contact angle (WCA), scanning electron microscopy (SEM), and X-ray photoelectron spectrometer (XPS) were used to characterize the MOF@CAA membranes. In addition, the antibacterial properties, pure water flux and dye/salt fractionation properties of the membrane were studied in detail. MOF@CAA LNMs has a porous surface and a sponge-like cross-sectional structure. The membrane has a reasonable water permeability (65.3 L/m2h), a rejection of 99.2 % for Congo red (CR) and almost zero rejection to inorganic salts (CR concentration: 100 mg/L, inorganic salts concentration: 1000 mg/L, operating pressure: 0.2 MPa). In addition, the MOF@CAA LNMs reduced 99.70 % of E. coli and 99.69 % of S. aureus in the bacterial suspensions. It is also found that the release of Ag+ion from the MOF@CAA LNMs is stably maintained at 0.1 μg L−1day−1for a period of 30 days. As the Ag nanoparticals (NPs) presented in the membrane were stably wrapped in UiO-66-NH2, its release could be maintained at a very slow rate continuously to achieve the purpose of controlled release and long-term sterilization.

Polytetrafluoroethylene (PTFE) is considered as one of the most promising membrane materials for oil-water separation, mainly because of its excellent chemical and mechanical stability. But its inherent strong hydrophobicity, which can cause the membrane easy fouled by bacteria, limits the application of PTFE membrane. We designed a new surface modification approach, through which hydrophilic and antibacterial PTFE membranes can be fabricated conveniently by combining polymerized dopamine (PDA) and thiolactone chemistries. A copolymer (P(DMAEMA-co-TlaAm)) containing thiolactone and tertiary amine moieties were synthesized by reversible addition–fragmentation chain transfer (RAFT) polymerization and attached onto the PDA coated PTFE membrane surface, together with glucosamine, via the thoilactone chemistry. Due to efficient glycosylation, the membrane exhibits great hydrophilicity. Water contact angle of the membrane surface dropped from 123° to 13°. Pure water flux of the membrane reached 2490Lm-2h-1bar-1, which is 2.7 times that of the original membrane. Also, the separation efficiency of the iso-paraffin emulsion reached 97.5% at a membrane flux of 90Lm-2h-1bar-1. Notably, in addition to the hydrophilicity provided by glucosamine, the modified membranes also showed decent antibacterial property because of the introduction of tertiary amine groups. The bacteria inhibition rate against staphylococcus aureus reached 99%.