Treating waste with Waste: Construction of a renovated composite adsorbent from waste polyurethane sponge for...

Bisphenol contaminants (BPs) pose significant ecological and health risks. Transforming waste into functional adsorbents is crucial for sustainable development. This study valorizes waste polyurethane (PU) sponge into a ternary composite (PUDA@β-CD@EZ8) for efficient BP removal. The material ingeniously combines polydopamine (PDA) adhesion, β-cyclodextrin (β-CD) inclusion, and etched ZIF-8 (EZ8) microporosity, creating a synergistic "capture-chelation-enrichment" pathway. Response surface methodology (RSM) optimized the process, yielding high Langmuir adsorption capacities (287.77 mg/g bisphenol A (BPA), 234.85 mg/g bisphenol S (BPS), 248.33 mg/g bisphenol F (BPF)). The composite maintained >85% efficiency in a fixed-bed column and ∼90% after ten cycles, with minimal metal leaching (<0.024 mg/L). It performed robustly in various real water matrices. Combined XPS analysis and density functional theory (DFT) calculations confirmed a multi-mechanism process dominated by hydrogen bonding and π-π interactions. This work presents a sustainable, high-performance adsorbent, advancing both waste recycling and green water treatment.