Successful preparation of CeO₂-modified 2D boron nitride for enhanced dye and humic acid separation with ultrafiltration membranes

Water pollution poses critical global challenges, necessitating innovative water treatment solutions. This study presents a pioneering investigation into the well-prepared cerium oxide (CeO₂) onto two-dimensional hexagonal boron nitride (H-BN) nanosheets for enhancing polymer-based ultrafiltration membranes. The polyethersulfone (PES) membranes modified with H-BN@CeO₂ were successfully fabricated using different additive mass concentrations (0.2–3 wt%), showcasing substantial improvements in membrane properties, particularly at 2 wt%. Filtration and rejection assessments, for pure water, humic acid (HA), and Eriochrome Black-T dye (EBT) were conducted to evaluate membrane performance. Notably, M-2 membrane (with 2 wt% H-BN@CeO₂) demonstrated exceptional pure water permeance, reaching 567.1 LMH/bar, a 4.2-fold increase over the pristine membrane. Additionally, it exhibited high permeance of 400.7 LMH/bar for 50 mg/L HA and 339.0 LMH/bar for 30 mg/L EBT solutions at 1 bar, maintaining over 90 % rejection rates for both pollutants. Excellent flux recovery ratios of 94.6 % for HA and 88.0 % for EBT ensured membrane longevity and reusability. Long-term filtration studies further validated the exceptional performance and efficiency of H-BN@CeO₂/PES membranes. Characterization of used membrane suggests size exclusion and surface interaction as primary removal mechanisms. The optimized membrane demonstrated promising results as a pre-treatment unit for reverse osmosis seawater desalination. This study highlights the potential of H-BN@CeO₂ nanocomposites in enhancing PES-based membranes for sustainable water filtration solutions.