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• Zeolitic imidazolate framework 8 (ZIF-8)–graphene oxide modified with amine groups via post modification. • The fabricated membranes have a good antibacterial and antifouling properties. • The membranes an exhibits strong antibacterial activity against E. coli and S. aureus bacteria. • Antibacterial mechanism of the membrane was proposed. Biofouling is an inevitable obstacle that impairs the overall performance of polymeric membranes used in water and wastewater treatment. This research focuses on the development of a novel nanocomposite membrane incorporating an antibacterial agent which has the potential to diminish membrane biofouling. An antibacterial agent, zeolitic imidazole framework-8 decorated with graphene oxide (ZGO), was functionalised with amino groups via direct post-modification method using ammonium hydroxide solution. The modified sample was then incorporated into polyethersulfone (PES) matrix at different weight loadings to produce ultrafiltration hollow fibre membranes by phase inversion method. The surface hydrophilicity and roughness of the membrane were improved with additional incorporation of ZGO–NH. The filtration results indicate that the permeation properties of the composite membranes were significantly improved compared to unmodified PES membranes. The water flux of the composite membranes increased with increasing ZGO–NH amount. The optimum value of ZGO–NH content is 1.0 wt%, in which the water flux reached the maximum value at 95.49 L/m2 h, 64.0% higher than that of neat PES membrane while maintaining BSA rejection of >95.0%. Moreover, the modified membranes also exhibited impressive antifouling properties with a flux recovery ratio (FRR) of 84.4% which is significantly higher than that of unmodified PES membranes (57.1%). The composite membrane possessed antibacterial capability against Escherichia coli and Staphylococcus aureus , having an antibacterial rate of 81.1% and 85.7%, respectively. Our proposed approaches show an excellent antibacterial ultrafiltration membrane to overcome biofouling issues via membrane modification. [ABSTRACT FROM AUTHOR]

In this work, the novel imprinted zeolite (IZ) was synthesized, and its properties and performance in terms of adsorption of p -Cresol, which represent the protein-bounded uremic toxins in aqueous phase under phosphate buffer saline, were studied and compared with the synthesized zeolite-Y (ZeoY-S) and commercial CBV 100 zeolite-Y (ZeoY-C). The ZeoY-S was synthesized from sodium aluminate, NaOH, H 2 O and SiO 2 under aging for 24 h at room temperature and hydrothermal condition for 24 h at 100 °C, with an initial composition of 10SiO 2 :Al 2 O 3 :4Na 2 O:180H 2 O. The ZeoY-S has been modified by using the imprinting technology to produce the IZ via the use of p -Cresol as a template. The p -Cresol successfully imprinted on the zeolite-Y was proved through the multipoint Brunauer-Emmett-Teller (BET) and the performance of IZ that was compared to ZeoY-S and ZeoY-C. Based on the BET results, it proves that the pore size of IZ is in accordance with the target compound, which is p -Cresol at 0.79 nm. This modification was able to adsorb p -Cresol 2.5 and 3.5 times higher than ZeoY-S and ZeoY-C can, respectively. Langmuir and Freundlich adsorption isotherm models, together with the pseudo-first and -second order and intra-particle diffusion kinetics models, were used to investigate the adsorption behavior of p -Cresol on the zeolites. The IZ has 4.30 times greater competitive molecules than ZeoY-S and the properties of IZ were not influenced by the content of other phenolic group uremic toxins as competitive molecules. It can be concluded that the micropores of zeolite as adsorbent can be modified using the imprinting technology in order to increase its sensitivity and selectivity towards p -Cresol. Unlabelled Image • The IZ by p -cresol as an template and target analyte has been successfully synthesized. • IZ able to adsorb p -cresol 2.5 times and 3.5 times higher than ZeoY-S and ZeoY-C, respectively. • By the IPD model shows that imprinting technology increased the sensitivity adsorption behaviour. • The IZ could be applied as hemoperfusion on haemodialysis treatment. [ABSTRACT FROM AUTHOR]