Nanoporous dopamine/β-cyclodextrin PES-PMACZ/MOF modified membrane for high-efficiency, low-fouling extraction of microplastics and PCB 209 from synthetic landfill leachate

Abstract

This research focused on the development of 9 advanced Dopamine/β-Cyclodextrin modified polyethersulfone (PES) membranes, incorporating a polymer-coated magnetic activated biochar-zeolite composite (PMACZ) and NH₂-MIL-101(Al) metal organic framework (MOF) in varying proportions. Membranes were designed for extraction of microplastics (MPs) and Decachlorobiphenyl (PCB 209) from synthetic landfill leachate (SLL). Characterization of the synthesized membranes was conducted using scanning electron microscopy and energy dispersive spectroscopy (SEM/EDS), Brunauer–Emmett–Teller (BET) analysis, X-ray diffraction (XRD), and raman spectroscopy. The membranes were evaluated for permeate flux, rejection efficiency, and fouling behavior. The membrane exhibiting optimal performance was selected for further examination, including cyclic stability, rejection and release performance, and pH tolerance. The rejection tests revealed complete removal of MPs and PCB 209 in water, while in SLL, removal rates were 100% for MPs and 99.67% for PCB 209. A decline in removal efficiency was observed with increased cycles. However, this decline was not significant. Release performance tests indicated negligible release (0% for MPs and 0.32% for PCB 209 in RO water; 0% for MPs and 0.8% for PCB 209 in SLL). Release of MPs under reversed flow conditions simulating backwash demonstrated rates of 95% and 93%. Notably, removal efficiencies exceeded 96% across all tested pH ranges, with optimal performance observed at pH levels of 5–8 for MPs and pH 8 for PCB 209, achieving complete removal. The membranes exhibited high permeability, 20 % enhanced fouling resistance, and exceptional rejection of both contaminants, affirming their potential for application in landfill leachate filtration.